Welsh Regional Water Resources Planning and Development Strategy
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AAC NRA Awdurdod Afonydd Cenedloethol National Rivers Authority Rhanbarth Cymru Welsh Region
Welsh Regional Water Resources Planning and Development Strategy
Final Project Report
July 1994
B I N N I E PARTNERS CONSULTING ENGINEERS A sia n ta eth y r A m g y lc h ed d C y m r u E n v ir o n m e n t A g e n c y W a l e s
GWASANAETH LLYFRGELL A GWYBODAETH CENEDLAETHOL
NATIONAL LIBRARY & INFORMATION SERVICE
PRIF SWYDDFA/MAIN OFFICE
Plas-yr-Afon/Rivers House Parc Busnes Llaneirwg/ St Mellons Business Park Heol Fortran/Fortran Road Llaneirwg/St Mellons Caerdydd/Cardiff CF3 OLT
NR.A ^ a l e s
ENVIRONMENT Ac cNCY
106254 EXECUTIVE SUMMARY
The National Rivers Authority (NRA) has a statutory duty under the Water Resources Act 1991 to conserve, redistribute or otherwise augment water resources and secure the proper use of water resources. This duty does not relieve any water undertaker of the obligation to develop water resources for the purpose of performing any duty imposed on it by virtue of the Water Industry Act 1991. The NRA must have regard to the reasonable needs of all abstractors, particularly those of the water companies. Additionally, the NRA is charged as the guardian of the water environment.
This report provides a policy framework for a Regional Water Resources Strategy for the sustainable development and ongoing management of water resources in the Welsh Region until 2021. It highlights the major issues and makes recommendations concerning the basis for decisions within the Region. Specific consideration has been given to:
* the existing balance of resources and demands;
* future demands for public water supply (PWS), industry, and agriculture;
* the need to improve ‘low flow rivers’ resulting from overabstraction;
* the selection of water resource options needed to meet justified needs.
By virtue of the Region’s relatively abundant water resources several rivers in the Region are already major resource providers to other Regions and this could potentially increase. The proposed strategy has therefore been developed in parallel with the NRA’s National Water Resources Strategy, and strategic national resource development proposals affecting the Region arc addressed.
The Region's water resources are reviewed in Section 2. The Welsh Region, the third largest of the eight NRA Regions, receives higher rainfall than any of the English Regions and includes a large number of major regulated rivers which represent the principal surface water resource of the Region. Groundwater is also important in the Region, being a source of water for many small private abstractions. However, much of the-Region is underlain by impermeable strata and groundwater provides only a limited resource for public water supply resources. The licence exemption status of a large part of Western Wales with respect to groundwater abstractions has resulted in a lack of detailed information on these resources and demands. The Welsh Region is a major net exporter of water. Imports to and exports from the Region are described.
Section 3 identifies and quantifies current and historic demands for water, both human and environmental. Hydroelectric power generation is the largest user of water in the Region, although this is a non-consumptive use. Public water supply is the second largest user of water, with about 40% exported out of the Region. Other abstraction demands include industrial, agriculture and amenity and conservation. In addition to abstraction the Region’s rivers are important for several in-river demands. Navigation, angling and effluent dilution all make requirements on rivers. Equally importantly surface water and groundwater resources are required to meet the demands of the environment in the form of water for the soil, wetlands, rivers and estuaries.
WRWRS.REP/75F/27 June 1994 This leads on to the forecasting of future demands in Section 4. Future demands for public water supply are forecast under a range of scenarios incorporating assumptions about growth in domestic and commercial consumption, per capita consumption, metering and leakage reduction. A consistent, multiple-component methodology, based on one developed in the NRA’s national resources development strategy project, has been employed. This leads to a demand forecast envelope which delimits growth in public water supply demand, ranging from 2% decrease to a 22% increase in demand in the Region. Future demands for private abstraction are also forecast, based on historic trends and consultation with representatives of industry and agriculture. Only spray irrigation and hydroelectric power generation are forecast to increase significantly over the planning horizon.
The forecasts illustrate how sensitive the timing of new resource developments is to the assumptions made in the demand scenarios. Marginal demand for public water supply ranges from about 20 Ml/d to 100 Ml/d in 2021. Under the medium growth scenario demand is forecast to increase by about 6% producing a marginal demand of 28 Ml/d with deficits commencing in 1996.
In Section 5 options for meeting the forecast marginal demands are explored. This includes saving water (demand management), re-allocation of water (reduction in licensed entitlement and incentive charging), and making more water available (resource development). Most of the marginal demands could be met through demand management measures and local source development. Under the high growth scenario one new resource development is identified as being required.
Section 6 details the proposed water resources development strategy in the form of proposed water resources management policies and extensions to the public water supply network. Recommendations for further work by the NRA are also included.
WRWRS.REP/75F/27 June 1994 CONTENTS Page
GLOSSARY OF TERMS vi
1 INTRODUCTION 1 1.1 Background 1 1.2 Specific objectives of the project 1
2 REVIEW OF THE WATER RESOURCES OF THE REGION 3 2.1 Regional characteristics 3 2.2 Surface water resources 3 2.2.1 Section 20 Operating Agreements 5 2.3 Groundwater resources 7 2.4 Licensed abstraction in the Region 8 2.4.1 Licence-exempt areas in the Region 9 2.4.2 Surface water abstraction licensing policy 10 2.5 Public water supply resources 10 2.5.1 Source yields 11 2.5.2 Dwr Cymru resources 11 2.5.3 Wrexham & East Denbighshire Water Company resources 15 2.5.4 Chester Waterworks Company resources 16 2.5.5 Efficiency of use and constraints on yield 16 2.6 Private demands resources 17 2.7 Imports and exports of water 17
3 CURRENT AND HISTORIC DEMANDS FOR WATER 19 3.1 Introduction 19 3.2 General 19 3.3 Public water supply 21 3.3.1 Analysis of licensed quantity/yield/demand balance in 1992 21 3.4 Private demands 23 3.4.1 Private water supply 23 3.4.2 Power generation 23 3.4.3 Industrial 25 3.4.4 Agriculture 25 3.4.5 Fish farming 26 3.4.6 Amenity/Conservation 27 3.4.7 Other uses 27 3.5 In-river demands 27 3.5.1 Navigation 27 3.5.2 Angling and recreation 28 3.5.3 Aquatic ecology 28 3.5.4 Effluent dilution 29 3.6 Environmental needs for water 29 3.6.1 Water for the soil 29 3.6.2 Water for wetlands 29 3.6.3 Water for rivers 31 3.6.4 Water for estuaries 32 3.7 Regional water balance 32
4 FUTURE DEMANDS FOR WATER SUPPLY 34 4.1 Introduction 34 4.2 General 34
WRWRS.REP/75F/27 June 1994 i CONTENTS Page
4 FUTURE DEMANDS FOR WATER SUPPLY(CONT,D) 4.3 Regional Public Water Supply demands 34 4.3.1 Methodology for PWS demand scenarios 34 4.3.2 Assumptions underlying demand scenarios 36 4.3.3 Demand forecasts 39 4.3.4 Projected resources shortfall for PWS 40 4.4 Future demands for industry & agriculture 50 4.4.1 Power generation 50 4.4.2 Industry 52 4.4.3 Agriculture 52 4.4.4 Amenity/Conservation 53 4.5 Projected resources shortfall for private demands 53 4.6 Environmental deficits 59 4.6.1 Alleviation of low flows (ALF) 59 4.7 National water resource demands 61 4.7.1 Enlargement of Craig Goch 62 4.7.2 Other options 63 4.8 Afforestation 63
5 OPTIONS FOR A STRATEGY FOR WATER RESOURCES 65 5.1 Introduction 65 5.2 The options for saving water - demand management 66 5.2.1 Leakage reduction 66 5.2.2 Metering of domestic water use 67 5.2.3 Consumer education 68 5.2.4 Better design of water appliances 68 5.2.5 Industry 68 5.2.6 The National Abstraction Charging Scheme 68 5.3 The options for re-allocating water 69 5.3.1 Under-used licences and ‘inefficiently’ used licences 69 5.3.2 Incentive charging 69 5.4 Options for making more water available 69 5.4.1 Local source developments and extensions 70 5.4.2 Regulated rivers - use of spare unlicensed yield 70 5.4.3 Regulated rivers - Increases in yield 71 5.4.4 Inter-basin transfers 72 5.4.5 Conjunctive use schemes 73 5.4.6 Recommissioning of Schwyll source 73 5.5 Groundwater development 87 5.5.1 Use of minewaters as a resource 88 5.6 Use of effluent returns 88 5.7 Alternative water sources 89 5.8 Impact of barrage developments 89 5.9 Possible impacts of climate change on water resources 90
6 PROPOSED REGIONAL WATER RESOURCES STRATEGY 92 6.1 Introduction 92 6.2 Proposed policies for water resources management 92 6.2.1 Licensing of abstractions 92 6.2.2 Demand management 93 6.2.3 The reallocation of water 93
ii WRWRS.REP/75F/27 June 1994 CONTENTS
6 PROPOSED REGIONAL WATER RESOURCES STRATEGY (CONT’D) 6.3 Proposed extensions to public water supply network 93 6.3.1 Medium growth scenario 94 6.3.2 High growth scenario 94 6.4 Private abstractions 95 6.4.1 Spray irrigation 96 6.5 Recommended areas of further work 97
REFERENCES 98
BIBLIOGRAPHY 101
APPENDICES
A Terms of Reference A1 B The geology of the Region B1 C Licensed abstractions in sub-catchments Cl D Public water supply sources in the Region D1 E Comparison of licensed quantities and actual abstractions (1981-1992) El F Estimated gross abstractions in sub-catchments FI G Public water supply demand forecasts for supply zones (1981-2021) G1 H Private demand forecasts (1981-2021) HI I List of consultees U
LIST OF TABLES
2.1 Hydrometric data for principal gauging statiuns in the Welsh Region 4 2.2 Summary of licensed abstraction in the Welsh Region 9 2.3 Summary of PWS licensed quantities and yields 12 2.4 Exports from the Welsh Region above 1 Ml/d licensed quantity 18 2.5 Imports to the Welsh Region above 1 Ml/d licensed quantity 18 3.1 Licensed abstractions from non-tidal waters 1981-1993 19 3.2 Actual Abstraction Factors 20 3.3 Anajysis of 1992 licensed quantity, yield and demand figures 22 3.4 Dwr Cymru CUA 1992 PWS demand breakdown 23 3.5 Summary of discharge consents in Welsh Region 30 3.6 Residual flows to rivers in the Region 31 3.7 Residual flows to tide in the Region 32 3.8 Net Use Factors 33 3.9 Summary of current abstractions in the Region (excluding transfers) 33 4.1 Assumptions and combinations within demand scenarios 35 4.2 Dwr Cymru PWS demand forecast household numbers assumptions 38 4.3 WEDWC PWS demand forecast household numbers assumptions 38 4.4 CWC PWS demand forecast household numbers assumptions 38 4.5 Dwr Cymru PWS average demand forecast 41 4.6 WEWDC PWS average demand forecast 42 4.7 CWC PWS average demand forecast 43 4.8 Summary of PWS average demand forecasts for the Region (including exports) 44 4.9 PWS peak week demand forecasts for the Region 47 4.10 PWS peak week marginal demands in the Region 48 4.11 Low flow problem sites in Welsh Region 60
WRWRS.REP/75F/27 June 1994 iii CONTENTS Page
LIST OF TABLES (CONT’D)
4.12 Preferred options in the national resources development strategy 62 5.1 Summary of PWS marginal demands in 2021 65 5.2 Leakage levels in the Region in 1992 67 5.3 Option 1 - Local supplies in Hereford and Radnor area 74 5.4 Option 2 - Local supplies in North Dyfed area 75 5.5 Option 3 - Local supplies in Meirionnydd 76 5.6 Option 4 - Extension of Cowlyd Reservoir 77 5.7 Option 5 - Pump surplus water from Llyn Alwen to Llyn Brenig 78 5.8 Option 6 - Raise dam crest at Llyn Celyn by 1.5m 79 5.9 Option 7 - Llyn-y-fan Fach regulating reservoir 80 5.10 Option 8 - Raise top water level of Llyn Brianne by 2m 81 5.11 Option 9 - Tywi to Usk transfer I 82 5.12 Option 10 - Tywi to Usk transfer II 83 5.13 Option 11 - Tywi to Pembrokeshire transfer 84 5.14 Option 12 - Transfer Upper Conwy to Llyn Celyn 85 5.15 Option 13 - Recommission Schwyll source 86 C.l Licensed abstraction from groundwater in the Region in 1993 Cl C.2 Licensed abstraction from surface water in the Region in 1993 C2 D .l Dwr Cymru South East Division supply area sources D1 D.2 Dwr Cymru South West Division supply area sources D3 D.3 Dwr Cymru Northern Division (W) supply area sources D4 D.4 Dwr Cymru Northern Division (E) supply area sources D5 D.5 Wrexham & East Denbighshire Water Company supply area sources D5 D.6 Chester Waterworks Company supply area sources D5 E .l Comparison of licensed quantities and actual abstractions for 1981 E4 E.2 Comparison of licensed quantities and actual abstractions for 1986 E5 E.3 Comparison of licensed quantities and actual abstractions for 1991 E6 E.4 Comparison of licensed quantities and actual abstractions for 1992 E7 E.5 Actual Abstraction Factors E8 F .l Estimated abstraction in 1993 from groundwater in the Region FI F.2 Estimated abstraction in 1993 from surface water in the Region F2 G.l PWS peak week low growth demand forecast Gl G.2 PWS peak week medium growth demand forecast G2 G.3 PWS peak week high growth demand forecast G3 G.4 Peak week marginal demands - low growth forecast G4 G.5 Peak week marginal demands - medium growth forecast G5 G.6 Peak week marginal demands - high growth forecast G6 H .l Power generation: HEP demands - low growth forecast HI H.2 Power generation: HEP demands - high growth forecast H2 H.3 Industrial demands - low growth forecast H3 H.4 Industrial demands - high growth forecast H4 H.5 Spray irrigation demands - low growth forecast H5 H.6 Spray irrigation demands - high growth forecast H6 H.7 General agriculture demands - low growth forecast H7 H.8 General agriculture demands - high growth forecast H8 H.9 Amenity/Conservation demands - low growth forecast H9 H.10 Amenity/Conservation demands - high growth forecast H10
WRWRS. REP/75F/27 June 1994 CONTENTS Page
LIST OF FIGURES
2.1 The Welsh Region Following 18 2.2 Sub-catchments and licence-exempt areas Following 18 2.3 Principal water resources of the Welsh Region Following 18 4.1 Dwr Cymru PWS average demand forecast 45 4.2 WEDWC PWS average demand forecast 45 4.3 CWC PWS average demand forecast 46 4.4 Summary of PWS average demand forecasts for the Region (including exports) 46 4.5 PWS marginal demands - low growth scenario 49 4.6 PWS marginal demands - medium growth scenario 49 4.7 PWS marginal demands - high growth scenario 49 4.8 Hydroelectric power demand forecast 54 4.9 Industrial demand forecast 55 4.10 Spray irrigation demand forecast 56 4.11 General agriculture demand forecast 57 4.12 Amenity/Conservation demand forecast 58 B.l The geology of the Welsh Region B.l G.l Water Company supply zones G.l
WRWRS.REP/75F/27 June 1994 V GLOSSARY OF TERMS
1:50 year Drought A drought of a severity which is likely to occur on average approximately once every 50 years.
£M Million Pounds Sterling
£K Thousands Pounds Sterling
AAF Actual Abstraction Factor.
Alleviation of Low Flows (ALF) The strategy for resolving environmental problems caused by over-abstraction in certain catchments.
Abstraction Licence Authorization granted by the NRA to allow the abstraction of water from a source of supply.
Aquifer A porous water bearing formation of permeable rock, sand or gravel capable of holding or transmitting significant quantities of water. Confined aquifer - where the upper boundary of the aquifer is largely sealed by overlying impermeable strata. Recharge can occur at those parts of the aquifer which are unconfined. Unconfined aquifer - the upper boundary of the permeable strata outcrops at the ground surface. Recharge occurs through rainfall or runoff.
(River) Augmentation To increase, support or regulate river flows by releasing or pumping from stored resources eg. reservoir or groundwater scheme.
Baseflow When rain falls onto a catchment, some water is absorbed by the soil instead of flowing directly to the river. The water reaches the river by slowly seeping through cracks and pores in the soil and rock. This is termed the ‘baseflow’ and provides the flow in a river during a long dry spell.
BW British Waterways
Catchment The area from which precipitation and groundwater will collect and contribute to the flow of a specific river.
Catchment Management Plan The planning process being used by the NRA with the aim of sustainable river basin development at a catchment scale.
Conjunctive Use Combined use of different sources of water (usually surface water and groundwater).
Conjunctive Use Area (CUA) • Term used to refer to an area in which the public water supplies are obtained from a group of sources operated conjunctively.
ewe Chester Waterworks Company.
vi WRWRS.REP/75F/27 June 1994 Demand The requirements for water by consumers. Average demand - usually refers to the average daily demand (averaged over the year) Peak demand - may refer to the seasonal peak consumption, peak week distribution demand, or peak daily demand recorded.
Demand Management Activities to manage the amount of water required from a source of supply; includes measures to control waste and/or to discourage consumption.
DCC Dee Consultative Committee.
Discharge Consent A licence granted by the NRA to discharge effluent of specified quality and volume at a specific point.
Drought A general term covering prolonged periods of below average rainfall resulting in low river flows and/or low recharge to groundwater, imposing significant strain on water resources.
Dry Weather Flow (DWF) For sewage works, this is calculated by adding estimates of domestic sewage discharge plus the industrial discharge plus the infiltration into the sewers.
EIA Environmental Impact Assessment.
Ecology The relationship between living systems and their environment.
Effluent Liquid waste from industrial, agricultural or sewage plants.
Effluent Re-use The use of effluent treated to appropriate (or required) standards for various uses from low grade (grey water) uses to potable supply. The term usually refers to indirect use of treated effluent - effluent mixed to a large degree with other raw water.
Effective Rainfall That rainfall ‘available’ for recharge of aquifers or to support river flows after losses due to evaporation and take up by plants.
EU European Union
Freshet Seasonal release of water.
GATT Global Agreement on Trade and Tariffs
Global Warming The generic term used to describe the climate changes which may occur for example, as a result of depletion of the ozone layer or through the emission of ‘greenhouse’ gases. ha Hectare
HEP Abbreviation for hydroelectric power.
HMIP Her Majesty’s Inspectorate of Pollution.
Hydrology The study of water on and below the earth’s surface.
WRWRS. REP/75F/27 June 1994 vii Groundwater Water held in aquifers.
1/hd/day Litres per head per day.
1/prop/hr Litres per property per hour.
Ml Megalitre
Ml/a Megalitres per annum.
Ml/d Megalitres per day.
MAFF Ministry of Agriculture, Fisheries and Food.
Marginal Demand A forecast demand for public water supply which cannot be met from existing sources.
NFFO Abbreviation for the government-led Non-Fossil Fuels Obligation scheme.
NFU National Farmers Union.
NRA National Rivers Authority.
NWWL North West Water Limited.
OFWAT Office of Water Services. OFWAT regulate charges of Water Companies and their service to customers.
PCC Per Capita Consumption or the quantity of water used for normal household domestic purposes expressed as a volume per person.
PE Potential Evapotranspiration
Public Water Supply (PWS) Water treated to potable standards, supplied to domestic and commercial consumers.
Q95 The mean daily flow of a river which is exceeded on average for 95% of the year.
R&D Abbreviation for research and development.
Regulated River A river where the flow is augmented through addition of water from another source.
SPL Supply pipe leakage.
SSSI -Site of Special Scientific Interest.
STWP Severn-Trent Water Pic.
SWQO Statutory Water Quality Objective
ToR Terms of Reference
viii WRWRS. REP/75F/27 June 1994 Water Table The level, in an aquifer below which the ground is wholly saturated with water. ^ ...... - '
Wetland An area of low lying land where the water table is at or near the surface for most of the time leading to characteristic habitats.
WEDWC Wrexham & East Denbighshire Waterworks Company.
Yield The reliable rate at which water can be drawn from a water source.
WRWRS. REP/75F/27 June 1994 ix 1 INTRODUCTION
1.1 BACKGROUND
The National Rivers Authority (NRA) has a statutory duty under the Water Resources Act 1991 (Ref 1) to "take such action as it may from time to time consider...... to be necessary or expedient for the purposes of conserving, redistributing or otherwise augmenting water resources and securing the proper use of water resources. This duty does not relieve any water undertaker of the obligation to develop water resources for the purpose of performing any duty imposed on it by virtue of the Water Industry Act 1991." The NRA must "have regard" to the reasonable needs of all abstractors and "have particular regard" to those of the water service companies and water supply companies. The NRA must also “generally promote” and, so far as is consistent with its other duties, "further the conservation of the water environment."
Increasing - and often conflicting - demands are made of the natural environment. These demands, working in concert with natural phenomena, can result in serious environmental problems. Water quantity, already reduced by abstraction, can be further reduced by drought. Water quality, affected by low river flows, is at greater risk from pollution by industry and agriculture. Polluted water puts aquatic life and abstraction for public supply at risk. Similarly complex interactions exist between river flow, underground water levels, and flooding, channel morphology and navigation, water quality and recreation. These demands and their interactions make the protection and improvement of the water environment, the NRA’s core business, an increasingly delicate balancing act.
Under Section 188 of the Water Resources Act 1991 the NRA is required to "...collate and publish information from which assessments can be made of the actual and prospective demand for water, and of actual and prospective water resources, in England and Wales". The overall objective of this project has been to respond to this Statutory requirement for the Welsh Region of the NRA, through the production of a Regional Water Resources Planning and Development Strategy.
1.2 S P E C IF IC OBJECTIVES OF THE PROJECT
The Terms of Reference (ToR) for the project are included as Appendix A. The specific objectives are detailed below:
(i) Review the current development of water resources within NRA Welsh Region and their use in meeting existing demands for water;
(ii) Collate and review estimates of future demands for Public Water Supply (PWS) abstraction in the Region up to the year 2021, in 5 year steps, commencing 1981;
(iii) Collate and review estimates of future demand for all other water requirements which impact on the water resources of the Region (including those from outside the Region) up to the year 2021, in 5 year steps, commencing 1981;
WRWRS.REP/75F/27 June 1994 Page 1 (iv) Consider the scope and options available to formulate a sustainable policy. Provide a plan for developing and augmenting water resources, and ensuring their proper use, to meet existing and estimated future demands for water in Welsh Region to 2021;
(v) Compare the various options and proposals considered, take account of environmental impact and other relevant criteria, and give due weight to economic considerations;
(vi) Liaise with the Consultants undertaking the National Water Resources Development Strategy to provide Welsh Region input as necessary and ensure compatible development so far as is possible;
(vii) Take account of progress made on the NRA Welsh Region proposed Abstraction Licensing Policy and other associated National and Regional developments.
These objectives are steps to develop a strategy to ensure the water resources of the Welsh Region are managed in the most environmentally acceptable and sustainable manner.
Page 2 WRWRS.REP/75F/27 June 1994 2 REVIEW OF THE WATER RESOURCES OF THE REGION
2.1 REGIONAL CHARACTERISTICS
The Welsh Region of the NRA, which covers an area of 21,262km2 (Ref 2), is shown in Figure 2.1 at the end of this Section. Geographically, it is the third largest of the eight NRA Regions. The landscape is very diverse across the Region, from the distinctive mountainous areas of North Wales to the low lying coastal areas of the Gwent and Glamorgan levels. The Region is characterised by a large number of river systems which flow in deeply incised valleys, radiating from the central high ground. Much of the Region has thin soil coverage and limited aquifers. Rainfall therefore finds its way quickly to the sea, with little held back to provide baseflows to sustain river flows in dry periods. The Region’s river flows consequently tend to rise and fall quickly in response to rainfall.
The Welsh Region receives more rainfall than any of the English Regions, averaging 1313mm over the period 1961-1990 (Ref 2). Table 2.1 summarises hydrometric data for the principal gauging stations in the Region. After allowing for evaporation losses and water used by plants and vegetation, which amounts to approximately 425mm on average (Ref 3), the effective rainfall available to sustain river flows and recharge aquifers averages about 900mm per year. On average approximately 600m? /s, or 52000 Ml/d, of runoff flows to sea. In drought conditions effective rainfall is reduced by about one third because increased losses from evaporation have a disproportionately large effect on the smaller depth of rainfall that is received. It is at such times that pressure is placed upon the environment and abstractors.
About 70% of the Region’s population of around 3.1 million people (Ref 4) are located in Wales, with the remainder iocated in Hereford & Worcester, Shropshire, and Cheshire (Ref 5). After Scotland and Northern Ireland, Wales is the most sparsely populated region of the United Kingdom, although there is a marked contrast between the urban areas of the former mining and heavily industrialised valleys in the South and the largely agricultural communities in Mid and West Wales. Approximately 50% of the Region’s population is located in South East Wales (Ref 4), with Cardiff, Swansea and Newport having a combined population of about 0.6 million people. During the 1980s the population of Wales increased by around 70,000 with some of the rural areas growing at a faster rate than the industrialised urban areas (Ref 5).
The Region’s population distribution has a major influence on how the Region’s water resources are utilised. The majority of PWS abstractions are made from the lower reaches of a number of the Region’s larger rivers. These rivers are subject to a high degree of regulation, with river flows carefully managed to support both abstractions and in-river demands. The majority of effluent discharges are made to estuarial and tidal waters and are therefore lost from the Region’s water resources.
2.2 SURFACE WATER RESOURCES
The majority of effective rainfall runs to sea as river flow, mainly in winter. This provides no reliable resource unless there is storage for summer use. There are three ways in which major reliable supplies are obtained from surface waters in the Region:
WRWRS.REP/75FC7 June 1994 Page 3 Table 2.1 Hydrometric data for principal gauging stations in the Welsh Region
Hydrometric Study River gaugl ng stations Area Subcatch men i Average annual value No. Area Area Rainfall Runoff Losses MAF 095 (km*) No. River Location Oim") Gauged total mm mm mm m“/s m*/s 55 4355 Upper Wye 55007 Wye Erwood 1282.1 1387 895 492 36.37 4.5 Upper Wye 55025 Uynfi Three Cocks 132.0 982 540 442 2.26 0.16 Lugg 55003* Lugg Lugwardine 885.8 839 378 461 10.63 1.43 Lugo 55018 Frome Yarkhill 144.0 714 266 448 1.21 0.14 Monnow 55009* Monnow Kentchirch 357.4 1028 521 507 5.90 0.77 Monnow 55022* Trothy Mitchel Troy 142.0 870 352 518 1.58 0.13 Lower Wye 55023 Wye Redbrook 4010.0 4010.0 92% 1024 567 457 72.12 11.61 56 1830 Ebbw 56002 Ebbw Rhiwdaryn 216.5 1496 1061 435 7.28 1.43 Upper Usk 56004* Usk Uandetly 543.9 1494 977 517 16.85 2.35 Upper Usk 56012* Grwyne Millbroofc 82.2 1251 771 480 2.01 0.34 Lower Usk 56015* Olway Brook Otway Inn 105.1 963 427 536 1.42 0.1 Lower Usk 56001 Usk Chain Bridge 911.7 1389 962 427 27.81 4.16 Lower Usk 56005 Lwyd Ponthir 98.1 1439 999 440 3.11 0.62 Lower Usk L56008* Monks Ditch Uanwern 15.4 1346.8 74% 891 432 459 0.21 0.05 57 955 . Ely. 57009 Ely St. Fagans 145.0 1350 933 417 4.29 0.55 taff 57003* Talf Tongwynlais 486.9 1863 1365 498 21.08 4.03 Rhymney 57008 Rhyrmey LJanedeym 178.7 810.6 85% 1407 955 452 5.41 0.72 58 975 Neath 58002 Neath Resoh/en 190.9 2034 1522 512 9.21 0.67 Neath 58008 Dulais Cilfrew 43.0 1782 1391 391 1.90 0.24 Ogmore 58001 Ogmore Bridgend 158.0 1747 1265 482 6.34 0.91 Ogmore 58009 Ewemy Keepers Lodge 62.5 1347 913 434 1.81 0.38 Thaw 58011 Thaw Gigman &idqe 49.2 503.6 52% 1170 636 534 0.99 0.14 59 920 Louphor 59002 Lou cfi or Tir-y-tfail 46.4 1534 1351 183 1.99 0.3 Tawe 59001 Tawe Ynystanglws 227.7 274.1 30% 1695 1650 245 11.91 1.38 60 2135 Taf 60003 Taf Clog-y-Fran 217.3 1423 1059 364 7.30 0.77 Taf 60004* Dewi Fawr Glasfryn Ford 40.1 1462 978 484 1.24 0.11 Upper Tywi 60007* Tywi Dolau Hrion 231.8 1694 1319 375 9.69 1.87 Upper Tywi 60005 Bran Llandovery 66.6 1499 1047 452 2.22 0.11 Upper Tywi 60009* Sawdde Felin—y-c w m 81.1 1537 1210 327 3.11 0.4 Cothi 60002 Cothi Felin Mynachdy 297.8 1638 1202 436 11.35 0.84 Gwili 60010 Tywi Nantgaredig 1090.4 1573 1109 464 38.35 3.63 Gwili 60006* Gwili GlangvMli 129.5 1477.3 *9% 1613 1190 423 4.89 0.41 61 1420 N.Remb coast 61003* Gwaun Cilrhedyn Bridge 31.3 1532 1121 411 1.11 0.15 Cleddau 61002 E.CIedcfau Canaston Bridge 183.1 1441 1030 411 5.98 0.97 Cledcteu 61004* W.CIedcbu Redhill 197.6 412.0 29% 1293 859 434 5.38 0.65 62 955 Teifi 62001 Teifi Gian Teifi 893.6 893,6 94% 1349 999 350 28.30 2.92 63 785 Rheidol 63002* Rheidol Ltanbadarn Fawr 182.1 1790 1544 246 8.91 1.9 Ystwyth 63001 Ystwyth Pont Ltolwyn 169.6 1485 1088 397 5.85 0.58 Wyre 63003* Wyre Ltanrhystyd 40.6 392.3 50% 1085 760 325 0.98 0.05 64 1380 Dysynni 64002 Dysynni Pont-y-Garth 75.1 2195 1890 305 4.50 0.49 Dyfi.Lert 64001 Dyfi Dyfi Bridge 471.3 1915 1521 394 22.73 2.04 Dyfi.Leri 64006 Leri Dolybont 47.2 593.6 43% 1504 743 761 1.11 0.04 65 1300 Gwrfai 65004 Gwrtai Bontnewydd 47,9 2212 1520 692 2.31 0.29 Seiont 65006 Seiont Pebtig Mill 74.4 2411 1956 455 4.61 0.59 Dwylor 65007 Dwyfor Garndolbenmaen 52.4 2092 1517 575 2.52 0.23 Erch 65005 Erch Pencaenewydd 18.1 1409 1058 351 0.61 0.09 Glaslyn 65001 Glaslyn BeddgeJert 68.6 261.4 20% 3097 2654 443 5.77 0.52 66 1470 Clwyd 66001 Clwyd Pont-y - cam bwll 404.0 910 473 437 6.06 0.89 Clwyd 66002* Elwy f^nt yr Onen 220.0 1119 642 477 4.46 0.45 Conwy 66011 Conwy Cwm Llanerch 344.5 968.5 2214 1666 548 18.20 1.24 67 2290 Upper Dee 67001 Dee Bala 261.6 1844 1530 314 12.69 2.2 Upper Dee 67006 Alwen Druid 184.7 1321 844 477 4.94 0.63 Upper Dee 67029* Trystion Pen-y-lelin Faw 12.3 826 0.32 0.02 Middle Dee 67015 Dee Manley Hall 1019.3 1402 958 444 30.98 5.16 Middle Dee 67025* Clywedog Bowing Bank 98.6 879 472 407 1.48 0.5 Lower Dee 67008 Alyn Ponl-y-C^pel 227.1 1345.0 59% 919 332 587 2.39 0.47 102 495 Anglesey Total 21265 13289 ti2%
MAF — Mean annual Dow 095 - 95%ile flow * Gauging station no longa operational
Weighted average rainfall 1428 mm Long term regional average rainfall 1313mm Weighted average runoff 975 mm Regional ttn o lt 897mm % runoff for Region 68.3
Page 4 c:\job sV4432\gsar eas.wk3\27 - Jun - 94 (i) Abstractions from unregulated rivers These depend on a steady baseflow component throughout the year and use the natural groundwater and wetlands storage in catchments to maintain flows in the river by natural means, (eg. Afon Teifi);
(ii) Abstractions from regulated rivers Several major rivers are regulated from surface storage (eg. Rivers Dee, Tywi, Usk, Wye) or from groundwater (eg. Clwyd);
(iii) Abstractions from impounding reservoirs Reservoirs constructed in areas where geography and topography have combined to produce factors favourable to reservoir construction, filled by either natural inflow or from pumped storage (eg. Rivers Elan and Alwen).
Most rivers in the Welsh Region, which are capable of providing worthwhile supplies, are utilised in one of these ways. Many of the major abstractions are made at or not far above the rivers’ tidal limits.
Historically, a lack of local resources for PWS in the industrialised Midlands and North West England, as well as South East and North East Wales, led to the development of direct supply reservoirs in the sparsely populated uplands of Wales, such as the Elan and Taf Fawr/Fechan Valley reservoirs. More recently development has continued, but with river regulation schemes replacing direct supply reservoirs as a more efficient way of utilising resources. Industrial and agricultural abstractions are important, although more recently industrial demand has declined with the collapse of "heavy" industry, to be replaced by hydroelectric power generation (HEP) and agricultural spray irrigation.
The Wye catchment, the largest in the Region, is particularly important in resources terms. Approximately 20% of the Region’s PWS is obtained from the river (of which around 10% is exported for supplies in England). The Wye is also utilised for a large number of private demands, with about 50% of the Region’s abstractions for spray irrigation being made from the Wye.
The Usk catchment, which covers 20% of the Region’s area, is also of particular importance, accounting for a further 15% of the Region’s PWS resources and supporting nearly 30% of industrial demand in the Region.
The Dee, in the north-east of the Region, is the source of about 30% of all PWS obtained from surface waters in the Region. Much of this water is exported from the Region for supplies in the North-West Region. It is also important for private demands for fish farming and industry.
The Region’s high rainfall and runoff has led to its importance for HEP, which is concentrated in catchments in the north-west of the Region, with most HEP schemes found in the Glaslyn and Gwrfai catchments.
2.2.1 ‘Section 20* Operating Agreements
Historically, the high population density around the Region’s coastline has led to the development of regulation schemes on a number of the Region’s major rivers. Section 20 of the Water Resources Act 1991 enables agreements between the NRA and water companies concerning the operation of water resources schemes owned by the water companies. These agreements are commonly referred to as ‘Section 20 Agreements’.
WRWRS.REP/75F/27 June 1994 Page 5 Such schemes involve the NRA in defining operational control policies to meet the regulated water supply demands from these schemes. NRA involvement in the operation of water company schemes can enable a proportion of the resource to be licensed to other abstractors and also gives greater control over how releases can best be managed to protect or enhance the environment.
NRA Welsh Region has six such Agreements with Dwr Cymru, on the Rivers Dee. Tywi, Wye, Dwyfor, Aled and Clwyd. Agreements were originally proposed for the regulation schemes in operation on the Rivers Usk, Eastern Cleddau and Gwyrfai. These were not implemented due to economic considerations and, in the case of the Gwyrfai, the short length of regulated river (Ref 6).
The Section 20 Agreement sets out the management rules for the system and specifies the financial provisions between the NRA and the water company. Each Agreement is supplemented by an Operating Manual which details the procedures to be followed by both the NRA and water company to ensure the intentions of the licences and management rules are implemented by staff with a minimum of supervision. A consultative group, comprising representatives of the NRA and Dwr Cymru, exists to agree procedures for the release of regulation water and freshets for river management, procedures for emergencies, and to agree any updating and revision to the Operating Manual.
2.2 A A The Dee Agreement
The Dee Regulation Scheme is unusual in that the detailed application of matters formalised in Statutory Instruments and Licences is subject to the over-riding framework of the Dee & Clwyd River Authority Act 1973 (subject to minor modifications in parallel with the Water Resources Act 1991). Both detailed and general principles are set out in the Dee General Directions which are modified from time to time through the Statutory Dee Consultative Committee (DCC). The DCC comprises representatives of the NRA, Dwr Cymru, North West Water Limited (NWWL), Wrexham & East Denbighshire Water Company (WEDWC), Chester Waterworks Co. (CWC), and British Waterways (BW).
The general principles for river regulation relate to the definition of a maintained flow of specified magnitude and location whilst having due regard to mitigating floods, safeguarding fisheries, supplying BW with a specified quantity, and any other purposes which in the opinion of the NRA are appropriate and consistent with the purposes of the Scheme.
The Section 20 Agreement deals with the management rules necessary for the effective day-to-day operation between the NRA and Dwr Cymru of Llyn Celyn, Llyn Brenig and Alwen Reservoir within the Dee Regulation Scheme.
2.2.1.2 The Wye Agreement
The storage of the Elan Valley reservoirs is used to satisfy three specific requirements: Firstly, to provide a direct supply to Severn-Trent Water Pic (STWP). Secondly, to provide a direct supply to Dwr Cymru at Elan Valley. Thirdly, to provide river regulation releases to the River Wye during periods of low flow, and which facilitate PWS abstractions by Dwr Cymru at Monmouth and STWP at Lydbrook. The general principles covering the operation of the Regulation Scheme are dependent on storage in the Elan Valley reservoirs and the flow in the Wye at Redbrook.
Page 6 WRWRS.REP/75F/27 June 1994 2.2.1.3 The Tywi Agreement
Llyn Brianne is used to regulate the River Tywi to support PWS abstractions at Manorafon and downstream at Nantgaredig. There is provision for compensation water and freshet releases from Llyn Brianne for the river system, which is an important salmon and sea trout fishery for both commercial and angling interests.
2.2.1.4 The Aled Agreement
Llyn Aled and Aled Isaf provide storage for river regulation of the Afon Aled to support PWS abstractions by Dwr Cymru at Bryn Aled, compensation releases from Aled Isaf, a residual flow for part of the year downstream of the Bryn Aled abstraction, and freshet releases in autumn and winter for fisheries.
2.2.1.5 The Clwyd Agreement
Boreholes in the Permo Triassic Sandstone in the Vale of Clwyd are used as the principle source of water for river augmentation of the Afon Clwyd. In addition, a statutory provision allows augmentation discharges of water from the Alwen Aqueduct, which provides a significant import of potable water into the Vale of Clwyd. The augmentation discharges are particularly beneficial in enhancing the very low natural summer flows in the Afon Clwyd between Ruthin and the confluence with the River Wheeler.
2.2.1.6 The Dwyfor Agreement
Llyn Cwmystradlyn is the principal source for the Lleyn Peninsula. The reservoir storage is used conjunctively on a seasonal basis for both direct supply and river regulation which supports abstractions by Dwr Cymru at Dolbenmaen, diurnally variable abstractions at Brynkir Mill, and compensation water and freshet releases for a river system which is an important salmonid fishery.
2.3 GROUNDWATER RESOURCES
Groundwater is utilised throughout the Region ranging from small private abstractions to major industrial and PWS sources. A detailed map showing the geology of the Region in included as Appendix B. The karstic limestones of the Carboniferous represent one of the major aquifers in the Region (Ref 4). They are highly permeable as a result of well developed joint and fissure systems. Large yields are obtained from major spring resurgences of groundwater, which occur near the base of the sequence or along faults. The groundwater catchments in karstic limestone may bear little relation to surface topography.
The Permo Triassic Sandstone in the north-east of the Region is a major aquifer but is limited in its distribution within the area. Where it does occur it is exploited by industrial and PWS abstractions.
The Old Red Sandstone, which has minor aquifer status on a national level, is regionally important in sustaining a large number of small public and private supplies. Supplies from gravel deposits exist throughout the Region and are heavily exploited by both local industry and private abstractors. In most cases these deposits are in hydraulic continuity with surface water systems.
WRWRS.REP/75F/27 June 1994 Page 7 Other aquifer systems throughout the Region may have too limited storage capacity and geographical extent for them to be exploited for large scale PWS. They do. however, offer an important resource for many rural areas and have become increasingly used for spray irrigation purposes.
2.4 LICENSED ABSTRACTION IN THE REGION
NRA Welsh Region currently controls about 4100 licences for abstraction of water from surface waters and groundwater, with the current total licensed entitlement amounting to just under 30,000 Ml/d (averaged over 365 days). PWS demand accounts for about 10% of the total. Private demands - abstractions made by individuals or organisations for their own use as alternative (for reasons of cost, quality or convenience) to the PWS system - account for the remainder. Typical uses are industrial cooling water, spray irrigation, and HEP generation. Many households take their water from private domestic wells but, because these are very small in size, they are not generally licensable. These abstractions are unlikely to increase in number and are not addressed in this report.
For the purposes of this study abstractions from springs have been considered as groundwater abstractions. However, it should be noted that springs are important to both surface water and groundwater; springs feed the surface water source, but the groundwater is important in the protection of the source. Licences have been classified according to 10 categories of use specified in the ToR. The categories are listed below:-
* Agriculture * Amenity and Conservation * Electricity - cooling (non-evaporative cooling) * Fish farming * Hydroelectricity * Industrial (includes process and sand & gravel washing, milling, bottling water, sewage treatment, evaporative cooling) * Public water supply * Private water supply * Spray irrigation * Others (unspecified uses) * Transfers
Table 2.2 summarises the licensed average daily abstractions (averaged over 365 days) and peak abstractions (maximum daily quantity) from surface waters and groundwater, in each category of use. About 30% of the licences are for abstractions from surface waters, but these account for 98% of the total licensed quantity. The majority of the large number of licences for groundwater abstractions are for abstractions for agricultural use. About 24350 Ml/d (averaged over 365 days), or 80% of licensed abstraction is from non-tidal waters. These figures are based on information obtained from the NRA’s licence database in July 1993.
Licences equal to or greater than 1 Ml/d (averaged over 365days) were audited to avoid double-counting of multiple site licences and linked licences, and to identify and rectify any errors in the database.
In this study the Region has been divided into 40 sub-catchments. The licensed quantities in each sub-catchment are presented in Appendix C.
Page 8 WRWRS.REP/75F/27 June 1994 Table 2.2 Summary o f licensed abstract ion in the Welsh Region
Source Purpose No of Licensed quantity (Ml/d) licences Daily Daily Peak Average
Agriculture 48 1 1 Amenity/conservation 82 79 118 Electricity-cooling 2 49851 55071 Fish farming 62 447- 632: Hydroelectricity 37 I78033 24656? Surface Industrial 182 1480J 25404 Water Public water supply 148 2909 3127 Private water supply 122 < 1 1 Spray irrigation 520 17 179 Others 27 89 100 Transfers 23 1837 7816 SOURCE TOTAL 1253 29646 44679
Agriculture 2118 15 21 Amenity/conservation 5 < 1 1 Electricity-cooling 0 - - Fish farming 5 2 2 Hydroelectricity 0 -- Groundwater Industrial 138 72 121 Public water supply 117 * 2195 2605 Private water supply 386 2 3 Spray irrigation 81 3 22 Others 12 1 1 Transfers 7 10 24 SOURCE TOTAL 2869 323 452
REGION TOTAL 4122 29969 45131
Legend: 1 Includes 4979 Ml/d tidal abstraction ? Includes 10 Ml/d tidal abstraction ? Includes 93 Ml/d tidal abstraction 4 Includes 523 Ml/d tidal abstraction 5 Includes notional 15 Ml/d in licence-exempt area
2.4.1 ^ Licence - exempt areas in the Region
Abstractions are exempt from licence controls under the Water Resources Act 1991 in two areas in the Welsh Region: much of the west of the Region including most of Dyfed, Gwynedd and Anglesey is exempt for groundwater abstractions and the Upper Usk sub- catchment upstream of Llangynidr is exempt for minor surface water abstractions.
WRWRS.REP/75F/27 June 1994 Page 9 Figure 2.2, at the end of this Section, shows the licence-exempt areas and the sub catchment boundaries. These areas were designated by application to the Secretary of State for Wales for an order under the Water Resources Act 1963. Within the groundwater exempt areas, spring water is classed as surface water and its abstraction is controlled by appropriate licensing procedures.
No information is currently available concerning the minor surface water abstractions in the Upper Usk licence-exempt area. However, the NRA believe these abstractions are insignificant in this area.
A large part of the Region’s groundwater resources are located within the licence-exempt area of West Wales. Dwr Cymru are known to operate a number of PWS sources in this area, mainly in the south-west of Wales. Although information about these sources is not available, the NRA has identifed a number of sources with a total yield of 15 Ml/d. A notional licensed quantity of 15 Ml/d (averaged over 365 days) has therfore been included in Table 2.2 to represent these sources. The total volume of abstractions from groundwater in the licence-exempt area is likely to be somewhat larger than this figure. It should therefore be noted that the figures in Table 2.2 and Appendix C underestimate the utilisation of groundwater in the Region.
The current lack of controls on groundwater quantity within the licence-exempt area pose problems for an integrated approach to water resource management throughout the Region. However, the controls exercised by the NRA concerning water quality within these areas are not compromised by the licence exemption status.
2.4.2 Surface water abstraction licensing policy
The Welsh Region of the NRA currently does not have a formal abstraction licensing policy. The Region is now undertaking an R&D project to develop a consistent, simple methodology for the licensing of surface water abstractions. The methodology will provide a straightforward, robust quantitative system for the evaluation and determination of abstraction licence applications. The project will address how much abstraction should be allowed from a catchment (taking account of in-river needs) and the setting of residual flow and other conditions on licences.
2.5 PUBLIC WATER SUPPLY RESOURCES
The NRA currently licenses 265 abstractions for PWS in the Welsh Region, which account for about 13% of the total licensed quantity from non-tidal waters. Dwr Cymru is the principal provider of water supplies in the Region. CWC and WEDWC provide water supplies in North East Wales, with their boundaries almost entirely within the Welsh Region of the NRA. Additionally STWP and NWWL have supply areas which cross over into Welsh Region’s area.
The Welsh Region has a highly developed water resource infrastructure for PWS. This provides considerable.flexibility in the management of water resources across the Region through intra-regional transfers. The Region’s principal water resources are shown in Figure 2.3 at the end of this Section. The three Welsh companies depend almost entirely on abstractions within the Welsh Region. STWP and NWWL benefit from substantial exports from the Region.
Page 10 WRWRS.REP/75F/27 June 1994 2.5.1 Source yields
The quantity licensed at each source is not necessarily reliably available. The term yield is used to define the quantity an abstractor can rely upon from a source under design drought conditions, that is the uniform rate at which water can be drawn from the source throughout a dry period of specified severity without depleting the contents to such an extent that withdrawal at that rate is no longer feasible. Traditionally, yields are based on 1:50 year or 1:100 year design droughts.
AH PWS companies have levels of service proposed by the Office of Water Services (OFWAT), which are:
* a hosepipe ban on average not more than once in 10 years;
* need for voluntary savings of water on average not more than once in 20 years; and
* risk of rota cuts or use of stand-pipes on average less than once in 100 years.
Since 1985, D&r Cymru has used ‘operational yield* as a measure of the source yield. This takes account of the way sources would actually be operated in severe droughts. It includes the effects hosepipe bans and drought orders would have on reducing demand upon its sources. Operational yield is based on the worst historic drought on record rather than a design drought, although Dwr Cymru believe that for their sources the worst historic droughts are not dissimilar to a 1:50 year or 1:100 year drought (Ref 7). Another important point is the assumed end date of the drought. Dwr Cymru assume an end date in mid-October for river-regulating systems and river abstractions, and mid- November for direct supply reservoirs and groundwater sources and springs. The addition of such a dry tail to the drought used in the yield calculation adds to its severity, leading to operational yields being lower than traditional yields.
CWC takes nearly all its water from the regulated River Dee, just upstream of Chester Weir. This regulated river has a reliable yield based on a 1:100 year design drought, and is subject to complex operation rules controlled through the DCC. In drought conditions the DCC can set rules to reduce abstractions. As a result the reliable yield of the Dee is assumed to equal the licensed quantity.
WEDWC takes approximately 70% of its water from the River Dee at Bangor-is-y-Coed. The yield of this source is equal to the licensed quantity. The remainder of its 14 sources, which comprise a mixture of surface water, spring and groundwater abstractions, have yields based on a 1:50 year design drought. Table 2.3 summarises the total yield for PWS sources in the Region. Detailed information is given in Appendix D.
The NRA is currently developing a National Methodology for assessing Surface Water Yield on a consistent basis.
2.5.2 Dwr Cymru resources
Dwr Cymru’s resources comprise 41 supply zones which have been considered in 5 sub- divisional areas for the purposes of this project. The supply zones show only limited correlation to sub-catchment boundaries. Dwr Cymru has developed a number of conjunctive use areas (CUAs) in recent years. These schemes in effect provide water grids covering a large proportion of the Company’s supply area, and enable Dwr Cymru
WRWRS.REP/75F/27 June 1994 Page 11 to meet demands more efficiently. Dwr Cymru currently operate six CUAs.
Dwr Cymru is part way through a programme of phasing out smaller sources for which it is not economically viable to provide water treatment to satisfy EU requirements on water quality: of the 225 licences which the company currently holds for PWS, 86 small licences (flagged in Tables D.1-D.3 in Appendix D) with a total licensed quantity of 64 Ml/d (averaged over 365 days) are disused. Dwr Cymru’s reductions in yield are taken into account in the existing yield figures in Table 2.3 as the Company has already set the yield of these sources to zero. The 22 Ml/d source at Schwyll near Bridgend in South Wales (which poses particular water quality difficulties), and a number of small sources with licensed quantities between 1 Ml/d and 5 Ml/d (averaged over 365 days), are being retained on a standby basis for emergency use. Dwr Cymru plan to decommission the Schwyll source in the near future.
Table 2.3 Summary o f PWS licensed quantities and yields (excluding water fo r non- potable supplies)
Water Company Licensed quantity Yield (Ml/d) (Ml/d) Current Planned Current Planned 1993 1996 1993 1996 DC SE Division 1339.0 1339.0 647.1 647.1 DC SW Division 624.0 624.0 431.0 409.0 DC N Division (W) 118.5 118.5 96.5 96.5 DC N Division (E) 148.0 148.0 138.0 138.0 DC TOTAL 2229.5 2229.5 1312.6 1290.6 WEDWC 67.4 55.0 55.9 54.6 CWC 36.4 36.4 34.6 34.6 Region total 2333.3 2320.9 1403.1 1379.8
Dwr Cymru have strategic plans to make good the reductions in yield by 1996. To a large degree the development of CUAs is making it possible to phase out unsuitable sources without the need to promote new sources. It is important to remember that the yield of revoked PWS licences immediately becomes available for the issue of new abstraction licences for other purposes. In addition to the total yield of 1291 Ml/d for potable supply Dwr Cymru also has a yield of 196 Ml/d for non-potable supply. The CUAs and their principal sources for potable supply (yield greater than 5 Mid) are discussed below.
2.5.2.1 The Southern CUA
The Southern CUA. is the largest of the six CUAs, meeting nearly 50% of the Company’s demands. The principal sources supplying the Area are detailed in the table overleaf. Llandegfedd is a pumped storage reservoir, which is supported by regulation releases to the River Usk from Usk impounding reservoir. At times when there is water surplus to regulation requirements in Usk Reservoir this is used to augment the guaranteed direct supply to the SW Division, thereby reducing that Division’s demands on the regulated River Tywi. The Monmouth Intake is supported by the Elan Valley reservoir group and
Page 12 WRWRS.REP/75F/27 June 1994 Taf Fechan/Taf Fawr reservoir group. Talybont Reservoir is used for direct supply.
Source Yield Treatment Works (Ml/d) Llandegfedd Reservoir 234 Llandegfedd, Court Farm River Wye, Monmouth intake 125 Court Farm Taf Fechan reservoir group 71 Pontsticill Taf Fawr reservoir group 46 Llwynon Taiybont Reservoir 46 Talybont Castell Nos & Lluest Wen 11 Maerdy Reservoirs Llyn Fawr Reservoir 7 Tynywaun Grwyne Fawr Reservoir 7 Cwmtillery Carno Reservoirs 5 Carno Shon Sheffrey Reservoir 5 Nant-y-bwch Bulk supply from SW Division 22 Felindre TOTAL 579
2.5.2.2 Felindre/Schwyll CUA
The Felindre/Schwyll CUA, in the SW Division, which accounts for about 20% of Dwr Cymru's resources, comprises the principal sources shown overleaf.
The Cray source provides much more than the operational yield for most of the year, and the use of surplus Usk water at Bryngwyn treatment works means that it is rarely necessary to take water from the Manorafon intake. Both these factors help to conserve storage at Brianne Reservoir on the Afon Tywi.
Source Yield Treatment Works (Ml/d) River Tywi, Nantgaredig intake 227 Felindre, Capel Dewi River Tywi, Manorafon intake 36 Bryngwyn Cray Reservoir 20 Cray Usk Reservoir 13 Bryngwyn Lliw reservoirs 10 Felindre Headwaters of the River Loughor 7 Bryngwyn Less bulk supply to SE Division (22)
TOTAL 291 - -
WRWRS.REP/75F/27 June 1994 Page 13 2.5.2.3 Alwen/Bretton CUA
The principal sources supplying water to the Alwen/Bretton CUA are detailed overleaf. The new treatment works at Alwen is designed to treat water in excess of the operational yield of the reservoir. This means that, instead of spilling into the River Dee, surplus water from Alwen Reservoir can be treated locally and delivered by gravity to the CUA, with a consequent reduction in the quantity which needs to be pumped to the more expensive Poulton treatment works.
Source Yield Treatment Works (Ml/d) Alwen Reservoir 35 Alwen River Dee, Poulton intake 24 Bretton TOTAL 59
2.5.2.4 North Eryri/Ynys MOn CUA
A trunk main across the reconstructed Britannia Bridge allows mainland water to be used on Ynys M6n to supplement the yield of Alaw and Cefni impounding reservoirs. The principal sources supplying water to the North Eryri/Ynys M6n CUA are detailed below:-
Source Yield Treatment Works (Ml/d) Alaw Reservoir 26 Alaw Llyn Cwellyn 12 Cwellyn Cefni Reservoir 10 Cefni Ffynnon Llugwy Reservoir 9 Llandegai TOTAL 57
2.5.2.5 Hereford CUA
The Hereford CUA primarily relies on an intake on the River Wye which delivers water to Broomy Hill treatment works. The CUA includes the town of Leominster, the city of Hereford and large rural areas to the north and south of the city.
Source Yield Treatment Works (Ml/d) River Wye. Broomy Hill Intake 45 Broomy Hill
TOTAL 45
Page 14 WRWRS.REP/75F/27 June 1994 2.5.2.6 The Pembrokeshire CUA
The principal sources supplying water to the Pembrokeshire CUA are detailed on the next page:-
Source Yield Treatment Works (Ml/d) River E.CIeddau, Canaston intake 58 Bolton Hill River W.Cleddau, Crowhill intake 10 Bolton Hill Prescelly Reservoir 7 Presceli Allocation to non-potable supply (37) TOTAL 38
2.5.3 Wrexham & East Denbighshire Water Company resources
The current total available yield from WEDWC’s sixteen sources amounts to 56 Ml/d; 40.9 Ml/d from the River Dee at Bangor-is-y-Coed and a total of 15.1 Ml/d from small sources, which include seven small impounding reservoirs and a number of boreholes and springs. The supply from the River Dee is pumped to the Marchweil bunded raw water storage reservoir, which provides a buffer of several days supply against pollution of the River Dee. Water gravitates from Marchweil to Llwynon treatment works which supplies the most densely populated part of the Company’s area in and around Wrexham.
The second largest source is the Legacy treatment works which treats water from Ty Mawr and Cae Llwyd reservoirs, which have a yield of 3.4 Ml/d. Arrangements have recently been completed which allow the yield of Penycae reservoirs to be transferred to Legacy, thereby enabling WEDWC to abandon the smaller Penycae treatment works.
WEDWC, similarly to Dwr Cymru, has developed a conjunctive use scheme. The Company is completing the construction of pumping stations and trunk mains which will enable them to deliver River Dee water to those parts of their area which have previously beeji dependent on direct supplies from impounding reservoirs and groundwater sources.
The Company has a number of small sources where the introduction of a satisfactory level of treatment is problematic or abstraction is causing low flow problems. Closure of seven of the Company’s smaller sources, with a combined yield of around 2 Ml/d is planned. To offset the reduction in the Company’s resources associated with the closure of its Minera sources WEDWC are expected to apply to the NRA to increase the Company’s abstraction from the Dee at Bangor. This will result in the source yield increasing to 43.4 Ml/d. Overall, the closures and licence changes will result in a total yield of 53.8 Ml/d.
WEDWC’s area of supply extends as far north as the recent commercial development located 3km south of the centre of Chester. WEDWC’s area lies mostly within the Middle Dee sub-catchment, with the remainder in the Lower Dee sub-catchment. The progressive integration of supplies across the Company’s area means that it is no longer meaningful to consider their different pressure zones as discrete supply zones.
All abstraction by WEDWC are used and returned entirely within the Dee Catchment.
WRWRS.REP/75F/27 June 1994 Page 15 2.5.4 Chester Waterworks Company resources
Currently, CWC’s total available yield is 35 Ml/d. Plemstall borehole, located within the North West Region, has a yield of 1.6 Ml/d which is used to supply consumers in that Region, although there is a connection to the main part of the Company’s supply system within the Welsh Region. CWC’s area lies primarily within the Lower Dee sub catchment, with a small fraction in the lower Mersey catchment.
Except for Plemstall, the whole of CWC’s supply is drawn from an intake on the left bank of the River Dee, about 1km upstream of Chester weir. Water is pumped via a syphon under the river to the Company’s Broughton treatment works 1.5km east of the city centre. This Works has been progressively enlarged and modernised during the last 100 years. It now includes three raw water storage reservoirs, the latest of which was constructed after a major pollution incident on the River Dee in 1984 and has a capacity of 38 Ml.
The total raw water storage could now maintain supplies for more than 2 days during a pollution incident, but this would necessitate pumping water at a rate in excess of the licensed quantity in order to refill the raw water storage reservoirs after the incident. About 1.5 Ml/d of abstracted water is returned to the river. Because the supply area drains via Chester sewage treatment works into the tidal length of the Dee, below Chester weir, all present and future demand in the Company’s area is a net drain on the resources of the Dee catchment.
2.5.5 Efficiency of use and constraints on yield
Dwr Cymru and WEDWC have developed effective conjunctive use schemes which enable them to meet demands during dry years and to provide benefits to the environment by minimising their consumption of power and treatment chemicals in wet years. Since privatisation, despite the occurrence of successive dry summers, none of the three companies has imposed restrictions on supplies to their consumers, indicating efficient use of available resources.
The relationship between licensed quantity and yield for the principal categories of abstraction licensed to the three Welsh companies is described in more detail in Section 3 below. In genera! the yield of abstractions supported by river regulation schemes equates to the licensed quantity. For other classes of PWS abstraction - direct supply impounding reservoirs, unsupported river abstractions and groundwater abstractions - the licensed quantity has usually been set at a high enough figure to enable the undertaker to take full advantage of water available in the reservoir, river or aquifer following periods of above average rainfall. The operational yield for these types of source is generated by the quantity of water available at the end of a prolonged dry period, which will clearly be less than the quantity licensed on the foregoing basis.
This method of licensing makes it possible to prevent surplus run-off escaping to the sea from overflowing reservoirs, from not fully exploited unregulated rivers, or in the case of aquifers which become surcharged, from springs which start flowing in these conditions. The maximum use of gravity supplies from sources reduces the consumption of power for pumping and of chemicals for water treatment. This provides benefits to the environment which would not be achieved if licences were restricted to little more than the operational yield of all sources.
Page 16 WRWRS.REP/75F/27 June 1994 Because the operational yield, depends on the ability to use all the licensed quantity of water available at the abstraction point at the end of a prolonged dry period it would not be possible to grant new licences to other classes of abstractor if the water companies licensed quantities were to be reduced to figures closer to the operational yield. Examples of cases where the actual quantities abstracted greatly exceed the operational yield are reservoirs in under-reservoired catchments. These include Cray, Taf Fawr, Lliw, Ystradfellte and Alwen.
At Lliw, where the two reservoirs have an operational yield of 10.3 Ml/d, the daily quantity pumped to Felindre via Lliw from Nantgaredig has to be adjusted to take account of the inflow to the reservoirs from their direct catchment. On occasions the quantity abstracted from the Tywi at Nantgaredig is reduced by as much as 100 Ml/d following heavy rainfall. Full utilisation of the available run-off from the Taf Fawr catchment permits a reduction in the daily demand on Llandegfedd Reservoir, as a consequence of the trunk main links throughout the Southern CUA.
2.6 PRIVATE DEMANDS RESOURCES
In addition to PWS the Region’s surface waters and groundwater are utilised for agriculture, power generation, and other industry. These abstractions are made directly from rivers and boreholes, although the water companies meet some industrial demands. Private abstractions account for 87% of the total licensed quantity for abstractions from non-tidal waters. The reliable output associated with the 3850 or so licences for direct use, are not readily available. For strategic planning purposes the ‘broad-brush’ assumption is made that the yield available to private abstractors is 100% of the licensed entitlement.
IMPORTS AND EXPORTS OF WATER
The Welsh Region is a net exporter of water to England, with about one third of licensed PWS abstraction being used outside the Region. Table 2.4 summarises those licences which account for exports.
NWWL have a single licence for their three abstractions from the River Dee at Chester for transfers to Merseyside. The abstracted quantity in 1992 was 547 Ml/d. NWWL Ltd have a second licence for 47 Ml/d for water taken to Nantwich via the Llangollen canal; the 1992 abstraction was 37 Ml/d.
STWP purchase from Dwr Cymru all except 5 Ml/d of the direct supply yield of the Elan Valley reservoirs; abstraction in 1992 was 323 Ml/d. When the current refurbishment of the aqueduct to Birmingham has been completed the average demand will probably return to the net available yield of 335 Ml/d. The Company’s abstraction from the River Wye at Lydbrook is for transfer to the Forest of Dean/Gloucester area, with actual abstraction around 39 Ml/d. The 9 Ml/d of treated water from this source sold to Dwr Cymru goes to Ross on Wye.
There are also several small imports to Welsh Region from North-West Region and Severn-Trent Region, detailed in Table 2.5 overleaf.
WRWRS.REP/75F/27 June 1994 Page 17 Table 2.4 Exports from the Welsh Region above I Ml/d licensed quantity
W ater Sub-catchment & Licence Licensed Present Company Source number quantity yield benefitting (Ml/d) (Ml/d) NWWL Middle Dee * Llangollen Canal 67-05-057 47.0 47.0 Lower Dee * Dee at Chester 67-09-147 650.4' 650.4 * Neston boreholes 67-10-064 2.3 2.3 STWP Upper Wye * Elan Valley reservoirs 55-01-0074 359.4- 335.5 Lower Wye * Wye at Lydbrook 55-18-375 36.4* 36.4 * Spring at Lydbrook 55-18-257 4.0 4.0 * Big Well at Monmouth 55-21-256 4.5 4.5 TOTAL 1103.5 1080.1
1 excluding 36 Ml/d sold to Dwr Cymru at Heronbridge for non-potable supply 2 excluding 5 Ml/d used at Dwr Cymru treatment works 3 excluding 9 Ml/d sold to Dwr Cymru at Mitcheldean 4 licence held by Dwr Cymru
Table 2.5 Imports to the Welsh Region above 1 Ml/d licensed quantity
W ater Region and Licence Licensed Present Current Company Source number quantity yield demand henefitting (Ml/d) (Ml/d) (Ml/d)
CWC NW Region * Plemstall b/h 68-06-011 2.3 1.8 1.5 Dwr ST Region Cymru * Whitbourne 54-09-008 9.0 8.8 7.7 * Leintwardine 54-09-367 1.0 1.0 1.1 TOTAL 12.3 11.6 10.3
Page IB WRWRS. REP/75F/27 June 1994 Designed 0 Capyrtyt B m t k ftxtnen Date Dote Note The IrreU. ndudna the hertits and Traced: He. Nahre of RevMm Cr ■n. Q * d Rvwd. Ootc Reproduc*d from # » 69M Ordionce Sirvey lhadhoriwd reproduction nfrrnjB 1 £23t000 map «th the ptrmtmcn of the Cantroir O w i Copyn^t and may lead to 0/ H r Majesty* Stationary Office © Q-owi Copyn^it. proeeaitionor aW f u e w A y BMC * PARTfCRS GROSVENGR HOUSE REDH1 SUWEY licence No. 1054 KEY: Coastline NRA Welsh Region Boundary Main Rivers ______Hydrometric Boundaries □ Reservoirs Principal Urban Areas 6 4 Hydrometric Reference No SCALE 1 : 1.000,000 'X J I 1 I I t I I I l~ _ioo mi NATIONAL RIVERS AUTHORITY (WELSH REGION) Regional Water Resources Strategy The Welsh Region FIGURE 2.1 T5555nS33^TS APRL 94 E 8INNIE ^ PARTNERS 1:1.000.000 COISVlflSC CMOtHCCKS iSB-lc- 4432/06/04 © C o p p ty t B b n t ft Partners Dots: £ate_ Note The biits, n d u * T j ths hsrtrts and Rsproduc*d from ths 4 ? td O r t h r a S r* s y Uw Jhorissd rsprodxtion nfm gss 1 €25X100 map with ths psrmis«an of ths Cantrohr O w * Copyri^it and may Isod to 0» H r Mojsstys Stationary Office © O rvm Capyn^it prosseutionor a v i prsossdngs. BMC * PARTtEFS CROSVENOR HOUSE F G M l SURREY Liosnos Nix 1064 t - ANGLESEY 21 - UPPER TYWI 2 - UPPER DEE 22 - OOTH 3 - kOOLE DEE 23 - GWU 4 - LOWER DEE 24 - GOWER 3 - CLWYD 23 - LOUGHOR 6 - CONWAY 26 - TAWE 7 - GWRFAI 27 - NEATH 8 - DWYFOR 28 - AFAN 9 - GLASLYN 29 - OGMORE 10 - ARTRO 30 - THAW 11 - DYSYW 31 - ELY 12 - DYFI 32 - TAFF 13 - fs-e d o l 33 - RHYKTEY 14 - AERON 34 - EBBW 15 - TEFl 35 - UPPER USK 16 - NORTH PEkeROKESKKE 36 - LOWER USK 17 - CLEDOAU 37 - UPPER WYE 18 - SOUTH PEWBROKESHRE 38 - LOWER WYE 19 - TAF 39 - LUGG 20 - GWEMDRAETH 40 - MOWOW KEY: Coastline NRA Welsh Region Boundary Main Rivers Subcatchment Boundaries Underground Strata □ Licence Exempt Minor Inland Waters □ Licence Exempt □ Reservoirs 30 Sub—catchment Ref. SCALE 1 : 1.000.000 J p O ten t t t ? — 1~ I I ~ f NATIONAL RIVERS AUTHORITY (WELSH REGION) Regiond Water Resources Strategy Subcatchments and Licence Exempt Areas FIGURE 2.2 Stod oss^ te: APRL 94 BINNIE & PARTNERS 1:1.000.000 cossuitisc tssistes* 4432/06/02 9*4J2dOO/«r-r/«ube KAL - OEMS OCPT 15 /4/9* P w iy n tt I e Ccpyrl^H Btn* 4c Pa~tnr» Data; O a d n d r Dot* Not*: Tllo irrits. ndudng tho and dlpttw Of th* » 0»V# tfiovn in tNa Traced: Dot. art not to b « tefcan a* Chock « lUv. Nofcr* of R««tiion. Owv Ofcd Oat* I ORTH WEST WATER LTD Raproduoad from th* O rdnroa S vx v y l>*» BMC * PARTfCRS OWSVCNOR HOUSE I Uoanc* No. 1054 To North West Region KEY: 45 Abstraction in Ml/d (NRA) Operated and owned by NRA Operated under ‘Section 20' {*&) Agreement ------► General direction of transfers <2 ? Reservoirs operated as a group Ground water abstraction River abstraction RESERVOIRS Coastline NRA Welsh Region Boundary Water Company Supply Boundaries Divisional Boundaries Company Areas: Q o w r Cym ru Main Rivers Chester Waterworks Co. River reach affected by □ upstream regulation To Gkxjc ester | j Wrexhom & E.Denbighshire Principal Urban Areas Water Co. SCALE 1 : 1.000.000 i i - r - r I NATIONAL RIVERS AUTHORITY (WELSH REGION) I Regional Water Resources Strategy Principal Water Resources of the Welsh Region FIGURE 2.3 I -CitaJ nT------Oate ' ’ iOWoci APRL 94 iod. 1:1,000,000 B 1 N N 1 E & PARTNERS I C I«II£ C IS 0»I1IJ na JIO S W R HOUSE - MDM1 - M T 4432/06/03 JU 3 2 4 0 0 / < n r / « w M L OEMS OEPT I3/4/94 3 CURRENT AND HISTORIC DEMANDS FOR WATER 3.1 INTRODUCTION In order to develop a Regional Water Resources Strategy the demands made on those resources must be identified, and quantified where possible. This Section describes the demands made upon the Region’s water resources, both human demands - public and private abstractions, in-river demands (navigation, fisheries and recreation) - and environmental demands (rivers, wetlands, estuaries). Historic and current abstraction demands are estimated to gain a better picture of how the utilisation of resources has changed in the last decade or so, and to provide useful information for forecasting future demands. Estimates of abstraction demands are based on an analysis of licensed entitlement and abstraction returns in the years of interest, which is detailed in Appendix E. 3.2 GENERAL Table 3.1 summarises licensed average quantities in 1981, 1986, 1991, 1992 and 1993. These have been estimated from an analysis of licence issue dates for licences greater than 1 Ml/d. Table 3.1 Licensed abstractions from non-tidal waters 1981 '1993 Source Purpose Licensed quantity (Ml/d) 1981 1986 1991 1992 1993 Surface Agriculture 0 0 1 1 1 Water Amenity/Conservation 3 7 72 78 79 Electricity - cooling 6 6 6 6 6 Fish fanning 93 98 421 437 437 Hydroelectricity 17134 17162 17597 17694 17710 Industrial 936 951 956 957 957 Public Water Supply 2890 2890 2909 2909 2909 * Private water supply 0 0 I 1 1 Spray Irrigation 10 13 17 17 17 Other 0 1 89 89 89 T mnsfers 1825 1836 1836 1837 1837 Groundwater Agriculture 14 14 15 15 15 Amenity/Conservation 0 0 0 0 0 Electricity - cooling 0 0 0 0 0 Fish fanning 1 1 2 2 n Hydroelectricity 0 0 0 0 0 Industrial 61 67 72 72 72 Public Water Supply 170 196 219 219 219 Private water supply 1 1 2 2 2 Spray Irrigation 1 2 3 3 3 Other 0 0 1 1 1 Transfers 9 9 10 10 10 REGIONAL TOTAL 23156 23257 24226 24348 24365 WRWRS.REP/75F/27 June 1994 Page 19 The total licensed quantity has remained fairly stable over the last 12 years, with a 5% increase between 1981 and 1993. The majority of this growth has been in fish farming and amenity/conservation, with less than a 1% growth in licences for PWS over the period. As growth in demand is influenced by a large number of factors the reader should be wary of drawing conclusions from this low growth. It may be that, due to the 1970s predictions of massive rises in demand, large increases in licences were granted. As demands did not increase as rapidly no extra licences would have been required. Demands for water in the Region for the years 1981, 1986, 1991, and 1992 have been estimated from actual abstractions data held on the NRA’s licence database. To assess gross demands for the different categories of use for surface water and groundwater sources the returns data and licensed quantity data were compared in the years of interest. This analysis is detailed in Appendix E. From the results of the comparison analysis % multipliers, to be applied to the licensed quantity to give an estimate of gross demand, have been set for each category of use and source. These multipliers are referred to as Actual Abstraction Factors (AAFs). It should be noted that the returns data used in the analysis was not complete, with only about 50% of licensed abstraction accounted for. Consequently, estimates of actual abstraction should be treated with caution. Table 3.2 sets out the AAFs used to estimate the current and historic demands in the Region. Table 3.2 Actual Abstraction Factors Source Purpose AAF (%) 1981 1986 1991 1992 Surface Agriculture 65 65 65 65 Water Amenity/Conservation 35 28 40 40 Electricity - cooling 24 14 10 15 Fish farming 50 50 50 50 Hydroelectricity 50 40 69 67 Industrial 68 60 32 28 Public Water Supply 68 67 71 69 Private water supply 60 60 60 60 . Spray Irrigation 26 20 27 36 Other 5 5 1 1 Groundwater Agriculture 80 80 80 80 Amenity/Conservation 40 40 40 40 Electricity - cooling - - - - Fish farming 50 50 50 50 Hydroelectricity - -- - Industrial 63 49 49 69 Public Water Supply 65 59 57 59 Private water supply 60 60 60 60 Spray Irrigation 30 43 43 96 Other 50 50 50 50 Page 20 WRWRS.REP/75F/27 June 1994 3.3 PUBLIC WATER SUPPLY PWS accounts for about 13% of licensed quantity (excluding tidal abstractions), and is the second largest demand for water after HEP. Average demand in the Region is currently about 2200 Ml/d, of which approximately 40% is exported outside the Region. After rapid growth in the 1960s and 1970s the demand for PWS has increased rather less during the 1980s, with a 3% increase in gross demand between 1981 and 1993. Abstraction has remained at 60% - 70% of licensed quantity throughout the period. 1981 1986 1991 1992 1993 Licensed quantity (Ml/d) 3060 3087 3128 3128 3128 Estimated gross demand (Ml/d) 2076 2052 2200 2136 2182 3.3.1 Analysis of the licensed quantity/yield/demand balance in 1992 Table 3.3 summarises the results of this analysis. Average daily demand figures for 1992 have been taken from the Companies’ October 1993 returns to OFWAT, with maximum week figures taken as 6% higher for Dwr Cymru and 12% higher for WEDWC and CWC based on information received from the three companies. Of the total licensed quantity of 3128 Ml/d for PWS, 54% depends on abstractions from regulated rivers and 46% on abstractions from direct supply reservoirs, unregulated rivers, groundwater and springs. For Dwr Cymru abstractions from regulated rivers the yield is just under 100% of the licensed quantity. Exceptionally, the licensed quantities of 136 and 85 Ml/d for the Wye (Monmouth) and Eastern Cleddau (Canaston Bridge) abstractions are taken to have yields of 125 Ml/d and 58 Ml/d respectively, which reduces the yield from the total licensed quantity of 809 Ml/d from regulated rivers by 5%. The corresponding reduction in the yield from the total licensed quantity of 1055 Ml/d from unregulated sources is 36%. Taken together, these figures give for 1992 a yield for all Dwr Cymru sources which was 81% of the licensed quantity of 1870 Ml/d (excluding the Elan Valley licensed quantity and yield). CWC and WEDWC are predominantly dependent on licensed abstractions from the regulated River Dee for which the yield is approximately 100% of the licensed quantity. However, about 30% of WEDWC demands are met from other sources for which the yield is quoted as 57% of licensed quantity. For CWC the average daily demand is already 84% of the available yield and has already reached a level where the margin available to meet peak demands and outages is uncomfortably small. For WEDWC the percentages are very similar to those for Dwr Cymru discussed above. The average daily demand in 1992/93, for the Welsh Region as a whole, was 70% of the licensed quantity for PWS and 81% of the yield. In the maximum week, demand rose to 85% of the yield. These figures for the whole Region mask the fact that in some supply zones the maximum week demand was very close to the operational yield. The figures are considered to be more meaningful than the suggestion in the NRA Discussion Document (Ref 8) that there was a surplus of 26% of Welsh regional resources above the 1990 average demand (ie. that demand was 74% of resources). Dwr Cymru’s six CUAs supplied 84% of the total average daily demand for potable water during 1992, as shown in Table 3.4. WRWRS.REP/75F/27 June 1994 Page 21 Table 3.3 Analysis of 1992 licensed quantity, yield and demand figures Page 22 WRWRS. RE P/75 F/27 June 1994 Table 3.4 Dwr Cymru CUA 1992 PWS demand breakdown Supply Zone Average daily % total demand demand (Ml/d) Southern CUA 480 46.2 Felindre/Schwyll CUA 211 20.3 Alwen/Bretton CUA 52 5.0 North Eyri/Ynys M6n CUA 48 4.6 Hereford CUA 42 4.1 Pembrokeshire CUA 38 3.7 Sub-total 871 83.9 35 smaller zones 167 16.1 Dwr CYMRU TOTAL 1038 100 A further 138 Ml/d of non-potable water was supplied. 3.4 PRIVATE DEMANDS 3.4.1 Private water supply Private water supply, at about 2 Ml/d, accounts for less than 1% of the total licensed abstraction in the Region. Demand has grown only slightly between 1981 and 1993, with estimated abstraction about 60% of licensed quantity. 1981 1986 1991 1992 1993 Licensed quantity (Ml/d) 1 2 2 2 2 Estimated gross demand (Ml/d) < 1 1 1 1 1 The majority of private water demands are met from groundwater sources. As a large part of the Region is licence-exempt for groundwater abstractions the actual demand in this category of use is likely to be greater than the figures above indicate. It should be remembered that there are a large number of small abstractions for domestic supplies which do not require a licence. However, as this category of use is not significant in strategic water resources terms it is not considered further in this report. 3.4.2 Power generation 3.4.2.1 Hydroelectric power HEP is the largest user of water in the Region, accounting for about 70% of the total licensed quantity (excluding tidal abstractions). Over 90% of this demand is within the Gwrfai and Glaslyn sub-catchments. All types of HEP schemes which include a physical abstraction from the river by pipe or leat require an abstraction licence. In many cases an impoundment licence is also required where upstream water levels are controlled by the scheme. Under special statutory provisions for HEP no annual payment is required WRWRS.REP/75F/27 June 1994 Page 23 for schemes generating less than 5 Megawatts. Nevertheless the duties imposed on the NRA by the issue of a HEP licence are substantial. HEP comprises recirculation water schemes and conventional HEP schemes. Three major recirculation water schemes in the Region - Dinorwic and Ffestiniog pumped storage schemes, and Trawsfynydd nuclear power station - account for 87% of the licensed quantity. Trawsfynydd power station is currently being decommissioned, and the licensed quantity is to be reduced from 3534 Ml/d to 639 Ml/d. All three schemes depend on impounding reservoirs, constructed by the generating companies, dedicated to power generation. As they have no significant impact upon the water resources of the Region they have been excluded from both the analysis detailed in Appendix E and the forecasts of HEP demand. There are 34 conventional HEP licences which account for about 26% of the total licensed quantity (excluding the three pumped storage schemes). Scheme sizes vary from less than 10 Ml/d to 1000 Ml/d. Several schemes in the range 25 Ml/d to 125 Ml/d have been licensed during the last 6 years. This has primarily been prompted by the Non- Fossil Fuels Obligation scheme (NFFO). The NFFO is a Government led initiative set up to ensure that regional electricity companies receive a proportion of their demand from non-fossil fuel sources. The NFFO offers incentives for the construction of relatively small HEP schemes in the form of subsidies towards construction costs and a guaranteed price for all power produced, regardless of the minimum quantity or time of day. The NFFO has made many small "run of river" schemes viable for the first time. HEP schemes at Dolwyddelan and Afon Hwch were commissioned in 1992, and at Aberdulais and Swansea Barrage in 1993. Recently licensed schemes at Afon Idwal and Penmancho Mill have yet to be built. The third round of bids to the Non Fossil Purchasing Agency had a deadline of 9th March 1994. Gross demand is estimated to have increased by 75% between 1981 and 1993. 1981 1986 1991 1992 1993 Licensed quantity (Ml/d) 1894 1922 2357 2361 2377 Estimated gross demand (Ml/d) 947 769 1626 1582 1664 Although water is generally discharged through turbines without loss in quantity, the operation of HEP schemes can create river management problems, causing severe damage to the aquatic environment and its users; a fact which can offset the benefits of the ‘clean’ energy produced. Associated with such schemes the operation of sluice gates to impound or release water can produce unacceptable variations in river levels and flow which can result in potentially serious consequences for other water users and for fisheries. The steep, fast-flowing upland rivers of North Wales are particularly attractive for HEP development because of the high heads and relatively high flows. Up to thirty potential sites have been identified by promoters to date, with proposals to abstract up to the average daily flow. There is a clear, unfulfilled demand for small scale high head HEP. There are likely to be two more NFFO rounds in the next two years. The abstractions can, in some instances, be made with minimal environmental impact, particularly where there is little distance between abstraction and discharge points and there is an adequate residual flow between the two. It is NRA policy to oppose a proposal where long reaches of river are bypassed, with attendant problems for water quality, fisheries, conservation, recreation, amenity, and other abstractors. Page 24 WRWRS.REP/75F/27 June 1994 3.4.2.2 Electricity - cooling water (non-evaporative cooling) There is an established network of strategic national power stations located around the coastline using sea-water for cooling purposes. National Power Pic has a licence for 4979 Ml/d for South Pembrokeshire power station, but this is a tidal abstraction. National Power also operates a power station at Aberthaw which takes water for cooling from the sea and is therefore not subject to licensing. The only licence for non- evaporative cooling water from non-tidal waters is in the Gwrfai sub-catchment, and relates to cooling water for cable ducts for Dinorwic power station. 1981 1986 1991 1992 1993 Licensed quantity (Ml/d) 6 6 6 6 6 Estimated gross demand (Ml/d) 1.5 0.9 0.6 0.9 0.9 Between 1981 and 1993 gross demand for electric-cooling water fell by about 35%. Consumptive use is very small, with most water returned to Llyn Padarn. 3.4.3 Industrial Industrial demands form a significant component of water resources demand in the Region, accounting for about 5% of total licensed quantity in the Region. There is a wide range of industrial uses of water ranging from almost wholly non-consumptive uses such as mineral washing to almost wholly consumptive such as top-up cooling water. 1981 1986 1991 1992 1993 Licensed quantity (Ml/d) 997 1018 1027 1029 1029 Estimated gross demand (Ml/d) 675.2 603.4 340.8 317.3 317.3 Whilst licensed abstraction has increased slightly between 1981 and 1993, gross demand has fallen dramatically from about 70% to 30% of licensed abstraction. This is in line with a national downward trend in industrial demand over the past 12 years, with the Wefsh Region experiencing a significant decline in heavy industry. The reasons for this decline are complex, with significant effects attributable to the general fall in industrial production, plant closures, and economic downturns. The NRA’s Charging Scheme for Discharges, introduced in 1991, has also probably had an impact on industrial abstractions. Under the scheme charges are made in respect of applications and consents for discharges to controlled waters, with the charge depending upon discharge volume, content and receiving waters. The scheme encourages dischargers to increase water recycling and use water more efficiently, and indirectly acts as an incentive to reduce abstractions. It should also be noted that some industrial demands are met by the water supply companies. 3.4.4 Agriculture 3.4.4.1 Spray irrigation Unlike many other uses virtually all water used is lost, either by evaporation or crop WRWRS.REP/75F/27 June 1994 Page 25 transpiration. 1981 1986 1991 1992 1993 Licensed quantity (Ml/d) 11 15 19 20 20 Estimated gross demand (Ml/d) 3.01 4.86 5.66 8.85 8.85 Licensed spray irrigation (averaged over 365 days) has increased from 11 Ml/d in 1981 to about 20 Ml/d in 1993. with peak abstraction rates very much higher (about 200 Ml/d in 1993). Between 1981 and 1993 gross demand has increased from 30% of licensed abstraction to about 45% of licensed abstraction. Spray irrigation currently accounts for less than 1 % of total licensed quantity. However, it has a significant impact on the water environment because demands occur over a short period when resources are least and demands are not uniformly distributed regionally but are concentrated in the Lower Wye, Lugg and South Pembrokeshire sub-catchments. Whilst the Welsh Region did not suffer from severe water shortages as experienced in the south-east of England in the 1990 to 1992 drought, spray irrigation demands in 1992 were significantly higher than in 1991. with a marked increase in abstractions from groundwater. The NRA now lays down conditions in new spray irrigation licences for abstractions from surface waters. These allow the NRA to restrict or prohibit abstraction when river flow measured at a control point falls below a prescribed value. 3.4.4.2 Other agriculture (excluding fish-farming) The demand for general agricultural use in regional resources terms is small. Abstractions are mostly less than 20 nvVday and do not therefore need a licence if they are from surface waters. 1981 1986 1991 1992 1993 Licensed quantity (Ml/d) 14 14 16 16 16 Estimated gross demand (Ml/d) 10.99 11.16 12.79 12.85 12.85 Licensed abstraction, at 16 Ml/d, accounts for less than 1 % of total licensed quantity for the Region, with the majority of demand met from groundwater sources. The water is used for general purposes in connection with dairying, food processing and where farmers depend upon springs and wells for domestic and general farm use. Unlike PWS, agriculture has no water infrastructure and individual farmers generally have to obtain water on or adjacent to their farm as best they can. Agricultural demand has remained fairly static between 1981 and 1993 at about 70% of licensed abstraction. However, it should be remembered that there may be a significant demand on groundwater resources in the licence-exempt area of West Wales. 3.4.5 Fish farming Fish farming has grown significantly over the past 12 years, and now amounts to about 2% of total licensed quantity in the Region. Gross demand is estimated to be 50% of licensed abstraction, with virtually all water returned to the river. Page 26 WRWRS.REP/75F/27 June 1994 1981 1986. 1991, 1992 1993 Licensed quantity (Ml/d) 93 99 423 439 439 Estimated gross demand (Ml/d) 46.63 49.56 211.29 219.36 219.36 Amenity/Conservation 1981 1986 1991 1992 1993 Licensed quantity (Ml/d) 3 7 72 78 79 Estimated gross demand (Ml/d) 1.20 1.91 28.71 31.27 31.67 Amenity/Conservation is also a small demand on resources, accounting for under 1 % of licensed abstraction in the Region. There has been a large increase in demand between 1981 and 1993, accounted for by a single licence in the Ebbw sub-catchment for the National Garden Festival of Wales. 3.4.7 Other uses 1981 1986 1991 1992 1993 Licensed quantity (Ml/d) 1 1 89 89 90 Estimated gross demand (Ml/d) 0.26 0.28 1.15 1.15 1.15 Other uses includes all minor unspecified abstractions, and amounts to less than 1 % of licensed abstraction in the Region. 3.5 IN-RIVER DEMANDS In addition to the abstraction demands made upon the Region’s surface waters and groundwater navigation, angling and recreation, conservation and the general aquatic environment, and effluent dilution all make demands for water. 3.5.1 Navigation Navigation requires level as well as flow. There are several canals in the Region, constructed between 1760 and 1840 under the Canal Enabling Legislation. Canals are used primarily for amenity and navigation purposes, but some are also utilised for transfer of water across watersheds for PWS. BW operates two canals in the Region: Llangollen Canal and Brecon & Monmouth Canal. BW do not require a licence for abstractions from surface waters to its canals under current legislation for the purpose of navigation. Additionally, BW hold licences for abstractions from the Brecon & Monmouth Canal and Swansea Canal for water which they seli on to third parties under their own charging scheme. ' ...... - - . WRWRS.REP/75F/27 June 1994 Page 27 The Llangollen Canal is the longest running transfer scheme in the UK, and feeds the Shropshire Union Canal system in Severn-Trent Region. BW abstracts its water from the River Dee; about 20 Ml/d for operational purposes, and about 40 Ml/d for transfer to Hurleston for NWWL as detailed in Section 2.7. The Brecon & Monmouth Canal runs along the Usk valley. An unlicensed canal feeder at Brecon is the primary source of water for the canal, with minor tributaries of the Usk and the Lwyd used to a lesser extent. The canal is believed to be used only for amenity purposes. The canal has a dramatic effect on the River Usk, particularly at times of low flow. Also, as the Usk is regulated on a put and take basis with a release from Usk Reservoir and subsequent abstraction downstream at Prioress Mill for Llandegfedd Reservoir, this canal feeder can intercept this release. 3.5.2 Angling and recreation Angling and recreation are important human uses of water, but with a demand that cannot be measured in the same way as abstractive uses. It is assumed that the needs of angling and recreation will be met if rivers are sustained in a healthy state, ecologically and aesthetically. Regulation has had a significant impact on fisheries and recreation in certain rivers in the Region, due to changes in the flow regime, water temperature, water quality and sedimentation. Alterations to the flow regime - steady higher summer flows and dampening of flood events - has resulted in a loss of spawning habitats and a reduction in the number of adult fish returning to spawn. Studies on the River Dee (Ref 9) have shown a reduction in salmon activity because of this phenomenon. Regulation can lead to a reduction in water temperature, which is likely to have a damaging effect on coarse fish populations, although some species may benefit from this change. Changes in water quality can also lead to reduced juvenile salmonid recruitment as seen on the Dee. Increased sedimentation due to organic enrichment of impounded waters may impact on salmonid egg survival downstream. Controlled releases can benefit recreational activities, such as on the River Tryweryn where regulation releases are utilised for canoeing. However, fisheries and recreation can make conflicting demands on regulation releases. The Section 20 Agreements between the NRA and Dwr Cymru contain provisions for freshet releases to safeguard fisheries, at such times and for such durations as requested by the NRA, subject to exceptional over-riding operational constraints. In addition, NRA and Dwr Cymru may arrange opportunistic river management releases when reservoir storage conditions make it possible. Smolt stocking schemes have been introduced to mitigate the loss of spawning and juvenile habitat. 3.5.3 Aquatic ecology . Research (Ref 9) indicates that regulation schemes in the Region have led to a reduction in the diversity of Benthic Macroinvertebrate fauna immediately downstream of reservoirs such as Llyn Brianne and Llys-y-fran Reservoir. Page 28 WRWRS.REP/75F/27 June 1994 3.5.4 Effluent dilution River flows are used not only as sources of water but also as diluters of effluent. There can be a conflict between abstractors and dischargers, who in effect compete to use the same water for incompatible purposes. It is necessary to try to maintain a balance between abstractors, dischargers, and the environment. Recent research (Ref 10) indicates that it is far more economic to achieve a given river quality by improving effluent treatment rather than increasing dilution flows. The NRA issues consents for discharges to rivers and tidal waters. A small number of discharges, those to tidal waters from power stations now fall under the jurisdiction of HMIP. Information on consents was retrieved from the NRA database and HMIP in October 1993. The database does not hold consented Dry Weather Flow (DWF) data for all consents, with only the Maximum Daily Volume (MDV) or ‘Flow in I/s’ given for over 50% of consents. Analysis of those consents for which values of DWF and MDV/‘Flow’ were available indicated that the consented DWF is a factor of 3.7 less than MDV/‘Flow\ DWFs were estimated for consents by application of this divisor to MDV/‘Flow\ Table 3.4 summarises the estimated total DWFs for all consents ^ 1 Ml/d MDV in the Region, Of the 14590 Ml/d total DWF only about 5% is discharged to non-tidal waters, with the majority of this from sewage treatment works. 3.6 ENVIRONMENTAL NEEDS FOR WATER There are four elements to the fresh water environment: * Soil water which sustains plants and trees * Wetlands/lakes * River flows * Estuary flows 3.6.1 Water for the soil Soil water is generally independent of the deeper water table from which abstractions are made, and is usually only in contact with groundwater along valley bottoms. It is affected by farm practices but is not generally in conflict with other water uses, and so is not considered further. 3.6.2 Water for wetlands Wetlands are areas where the water table is close to or at the surface. They can be important in maintaining baseflows, as evidenced by Tregaron Bog on the Upper Teifi, and are also seen as important buffers for water quality purposes. Developments of all kinds have greatly diminished natural wetlands, and those remaining are rightly seen as valuable heritage. WRWRS.REP/75F/27 June 1994 Page 29 Table 3.5 Summary o f discharge consents in Welsh Region Subcatchineut Noii'tida) couseuls Tida) couseiils Combined Total Sewage Trade/Other Sewage Trade/Other No. DWF No. DWF No. DWF No. DWF DWF (Ml/d) (Ml/d) (Ml/d) (Ml/d) No. (Ml/d) Monnow 0 3 14.15 0 0 3 14.15 Lugg 9 9.37 4 11.42 0 - 0 - 13 20.79 Lower Wye 8 38.76 2 0.74 3 2.42 1 9.73 14 51.65 Upper Wye 5 3.46 2 2.27 0 - 0 - 7 5.73 Lower Usk 9 68.82 7 23.18 17 227.98 4 31.99 37 351.97 Upper Usk 4 5.40 3 2.85 0 - 0 - 7 8.25 Ebbw 0 - 6 9.58 3 80.22 0 - 9 89.80 Rhymney 0 - 1 1.17 0 - 0 - 1 1.17 Taff 5 57.94 17 44.58 4 283.66 0 - 26 386.17 Ely 11 32.17 2 4.69 1 1.35 1 2.16 15 40.38 Thaw 6 12.26 4 9.14 9 119.30 4 6103.64 23 6244.34 Ogniore 1 6.02 2 5.87 1 23.00 0 - 4 34.89 Afnn, Kenfig I 3.13 0 - 1 38.88 3 142.76 5 184.76 Neath 6 10.64 8 11.48 2 7.68 0 - 16 29.81 Tawe 5 20.90 7 13.05 0 - 2 5.93 14 39.89 Loughor 5 13.15 3 11.70 2 11.57 0 - to 36.42 Gower 6 29.51 2 7.15 12 61.89 2 3.69 22 102.24 GwiJi 2 1.32 1 0.37 3 5.96 0 - 6 7.65 Cothi 1 0.28 0 - 0 - 0 - 1 0.28 Upper Tywi 3 6.72 1 0.86 0 - 0 - 4 7.58 Gwendraelh 4 8.45 3 2.02 4 22.77 0 - 11 33.24 Tar 3 0.95 3 1.57 4 3.23 0 - 10 5.75 South Pembs 7 2.71 2 6.22 9 13.69 5 5626.03 23 5648.64 Cleddau 4 8.12 2 4.84 2 7.10 0 - 8 20.06 North Pembs 2 0.84 0 - 3 2.85 0 - 5 3.69 T e ifi 7 5.35 2 1.51 1 2.68 0 - 10 9.54 Aeron. Arth I 0.29 0 - 3 5.88 0 - 4 6.17 Rheidol 2 1.33 0 - 0 - 0 - 2 1.33 D y fi. Leri 3 1.88 1 0.28 1 1.19 0 - 5 3.35 D ysynni 0 - 1 0.29 0 - 0 - I 0.29 Anro. Mawddach 2 2.32 1 2.28 4 3.66 0 - 7 8.26 Glaslyn 2 1.36 I 0.93 5 5.40 0 - 8 7.70 D w yfo r 0 - 0 - 5 5.88 0 - 5 5.88 Gwrfai 9 5.81 3 4.90 11 28.69 2 91.33 25 130.73 Conwy 2 1.29 0 - 15 36.71 3 25.27 20 63.27 C lw yd 14 49.70 8 14.24 6 55.41 0 - 28 119.35 Low er Dee 18 36.93 10 5.40 9 41.68 6 13.50 43 97.51 M iddle Dee 7 51.09 11 29.09 0 - 2 1.56 20 81.75 U pper Dee 0 * 6 28.34 0 - 0 - 6 28.34 Anglesey 2 5.43 2 2.78 21 13.41 2 635.14 27 656.76 TOTAL 176 503.71 131 278.95 161 1114.14 37 12692.72 505 14589.52 Number of tidal consents ^ 1 Ml/d 198 Number of non tidal consents ^ 1 Ml/d 307 Volume of tidal consents ^ 1 Ml/d 13807 Ml/d Volume of non tidal consents 1 Ml/d 783 Ml/d Total consented volume 14740 Ml/d Percentage of consents ^ 1 Ml/d 99 % Page 30 WRWRS.REP/75F/27 June 1994 3.6.3 Water for rivers Rivers are naturally changing systems. They have been greatly changed by man over the centuries. Today a large number of the Region's major rivers are thoroughly unnatural, subject to a high degree of flow regulation. The character of a river depends on its flow, its quality, and the physical characteristics of its bed and banks. Flows are changed by abstractions, effluent discharges, water transfers, drainage improvements and regulation. The net effect is often to reduce middle range flows but increase low flows. Quality is changed by effluent discharges, land use, and transfers. Research has shown that moderate reductions in average flows are not generally ecologically significant. However there is a need to sustain acceptable minimum flow regimes. No objective criteria are yet established, although the NRA is currently undertaking research to define ecologically-acceptable flows (Ref 11). The Surface Water Abstraction Licensing Policy R&D project (See Section 2.4.2) will address this issue as part of the development of a consistent methodology for licensing. A provisional estimate that has been used in the interim is the natural Q95 flow - the flow that would naturally be equalled or exceeded for 95% of the time. In some catchments, where there is little or no artificial influence on river flows (abstractions and discharges), the ‘natural’ flow can be assumed to be equal to the gauged flow. Otherwise the ‘natural’ flow has to be estimated from gauged flow records and knowledge of artifical influences. In the Welsh Region many of the major rivers are subject to a great degree of artifical influence by way of the regulation schemes. Unfortunately, very few of these rivers have had their flow records ‘naturalised’. The Water Resources Act 1963 provided tor the setting of minimum acceptable flows (MAFs). The Water Resources Act 1991 restates this provision, with minor changes. However, no MAFs have been set in this (or any other) Region. A few minimum residual flows (MRFs) have been set instead, mostly as control flows, below which specific abstractions must cease. They have a similar effect to MAFs but without such legal connotations. Table 3.5 details the minimum residual flows to rivers in the Welsh Region. Table 3.6 Residual flows to rivers in the. Welsh Region River Locution M RF (Ml/d) Comments Tywi Nantgaredig 136.4 PWS Intake Usk Rhyadyr 228.0 PWS Intake to Wye Redbrook 1210.0 Llandegfedd E. Cleddau Pont Hywel 4.5 E. Cleddau Canaston weir 68.2 (variable) PWS Intake Afon Aled Bryn Aled 29.5 (variable) Natural flow at PWS 11.4 Intake Dwyfor Dolbenmaen 29.5 J un-Jan 59.1 Feb-May Afon Clwyd Pont y Cwmbwll 147.0 Sep-May Jun-Aug WRWRS. REP/75F/27 June 1994 Page 31 3.6.4 Water for estuaries The criteria for setting minimum flows to estuaries are different to those for inland waters. There are major abstractions at or near to the tidal limits of many the Region’s rivers. Most of these are subject to minimum residual flows for protection of the estuary. Table 3.6 lists the minimum residual flows to estuaries in the Region identified in recent research undertaken by the NRA (Ref 12). Table 3.7 Residual flows to tide in Welsh Region River Location MRF(MI/d) Comments Tywi Nantgaredig 136.4 PWS Intake Wye Redbrook 1210.0 Dee Chester weir 363.0 3.7 REGIONAL WATER BALANCE In some categories of use some, if not all, water is returned to the river after use. In order to assess the overall water balance for the Region the net demands of abstractors have been estimated. There is little information available to assess the amount of water returned to river, principally due to a lack of information on actual discharges. In order to estimate the net demand for water in the Region Net Use Factors (NUFs) have been set to estimate net demand, based on NRA R&D Note 35 Vol.2 (Ref 13) and recent work carried out on three rivers in Essex (Ref 14). The NUFs are shown in Table 3.7. In the case of PWS net demands are less than 100% reflecting the fact that it is assumed that 70% of these abstractions are returned to either non-tidal or tidal waters and 30% of sewage treatment works discharge to inland waters. Table 3.6 summarises the current licensed quantity, and estimated total and net abstractions in the Region, using the AAFs for 1992 with licensed quantities for 1993 and the NUFs shown above. Tidal abstractions are excluded as these do not draw upon the water resources of the Region. A breakdown of current demands at a sub-catchment level is given in Appendix F. The water balance for the Region can be expressed as follows: Balance = Gross regional resource - Net abstractions - Exports from Region - Minimum river flow It was explained in Section 2.1 that the effective rainfall under drought conditions is 600mm/yr. This equates to a gross regional resource of approximately 34700 Ml/d. The minimum river flow is used as a simplistic estimate of the resources which must be protected to meet environmental and in-river demands on rivers. Research is ongoing to establish ecologically-acceptable flows (See Section 3.6.3). In the absence of a readily applicable measure of this river flow it is conservatively estimated as being 50% of the gross regional resource (Ref 15). The NRA has recently undertaken research into ecologically-acceptable river flows and is currently looking into a methodology for application to rivers. Page 32 WRWRS.REP/75F/27 June 1994 Table 3.8 Net Use Factors Purpose or abstraction NUF(%) Agriculture 20 Amenily/Conservation 0 Electricity - cooling 0 Fish fanning 0 Hydroelectricity 0 Industrial 30 Public water supply (deluding exports) 80 Private water supply 80 Spray irrigation 90 Other 0 The regional water balance therefore becomes, Balance = 34,700 - 1067 - 934 - (0.5 x 34,700) = + 15350 Ml/d The positive water balance indicates that the Welsh Region is in a generally healthy state. This position will need to be reviewed once a methodology has been developed to assess minimum river flows. Table 3.9 Summary o f current abstractions in the Region (excluding transfers) Source Purpose Licensed Estimated gross Estimated net quantity abstraction abstraction (Ml/d) (Ml/d) (Ml/d) Surface water Agriculture 1 1 < 1 A menity/Conse rval ion 79 31 0 Electricity-cooling 6 1 0 Fish fanning 437 218 0 Hyd reeled ricity 17710 11865 0 Industrial 957 268 80 Public Water Supply 2909 2007 858' Private water supply 1 <1 < 1 Spray irrigation 17 6 5 Other 89 1 0 Groundwater Agriculture 15 12 2 Amenity/Conservation < 1 <1 0 Elect ricily -cooling - - 0 Fish fanning 1 0 Hydroeleelrieity - - 0 Industrial 72 49 15 Public Water Supply 219 129 103 Private water supply o 1 < I Spray irrigation 3 3 3 Other 1 < 1 0 REGION TOTAL 22518 14595 1067 1 excluding exports from the Region of 940 Ml/d WRWRS.REP/75F/27 June 1994 Page 33 4 FUTURE DEMANDS FOR WATER SUPPLY 4.1 INTRODUCTION This Section describes the predicted future demands for water that arise both within the Region and those at a national level. The potential changes in demand are identified, and shortfalls in existing available resources are estimated for a range of scenarios. The work the NRA is currently undertaking on the Alleviation of Low Flows (ALF) in the Region is also described. Forecasts of future demand for PWS are calculated using a multiple component methodology, developed for the NRA’s National Water Resources Strategy. A range of scenarios is considered, incorporating various assumptions about demand management, growth in domestic supply, and metering. Forecasts of future private demands are based on historic trends, available published information and consultation with representatives of industry and agriculture. 4.2 GENERAL Forecasts of demands for water have been made for the period 1996 to 2021 at five yearly intervals. Forecasts are based on trends in historic demands between 1981 and 1991, available information from the NRA, water companies, and County Structure Plans, and discussions with representatives of industry and agriculture. In the case of PWS, forecasts have been made at a supply zone level for Dwr Cymru, the principal water service company in the Region, and at a Company level for the two other water supply companies. Forecasts of private demands, for agriculture and industry, have been made on either a sub-catchment or regional basis as appropriate. 4.3 REGIONAL PUBLIC WATER SUPPLY DEMANDS 4.3.1 Methodology for PWS demand scenarios A multiple component methodology, based on that utilised in the NRA’s National Water Resources Strategy (Ref 16), has been used to forecast current and future PWS demand. Demand scenarios are described by a suite of broad based assumptions about future demand. The forecasts delimit the range of forecast between high and low and therefore indicate the predictive demand envelope. The base year has been taken as 1992, with the forecast horizon set at 2021. Calculation intervals are 5 years (with the exception of the first time step of 4 years) ie. 1996, 2001, 2006, 2011, 2016, 2021. The following data sources have been used for calculation of the forecast components:- * OFWAT October Returns to the Director General 1993; * OFW AT Cost of Water Delivered & Sewage Collected 1992-93 (Ref 17); and * Per capita consumption data from Binnie and Herrington (Ref 18). Page 34 WRWRS.REP/75F/27 June 1994 The various demand assumptions, combined to produce forecast scenarios which reflect a prediction envelope, are summarised in Table 4.1. Table 4.1 Assumptions and combinations within demand scenarios Assumptions for each scenario No. Assumptions High Medium Low Broad area of effect 1 Growth of PCC by compound annual rate ■ of 1%. Upper limit of 189 1/hd/day. PCC 2 Growth of PCC by compound annual rate m ■ growth derived from Ref 18. Upper limit of 180 1/hd/day. 3 Growth in metered and unmetered non ■ household consumption by compound annual rate of 0.75%. 4 Growth in metered and unmetered non ■ Commercial household consumption by compound growth annual rate of 0.5%. 5 No growth in metered and unmetered non- ■ household consumption above 1992 level. 6 Dwr Cymru - Metering of new properties ■ only if requested by the customer (Company policy) WEDWC - No metering of new properties from 1996 CWC - No metering of new properties from 1996. Metering 7 Dwr Cymru - Metering of new properties ■ from 2006 WEDWC - No metering of new properties from 2006 CWC - No metering of new properties from 2006. 8 Dwr Cymru - As high forecast plus all ■ new properties metered WEDWC - All new properties metered (Company policy) CWC - All new properties metered (Company policy). 9 Leakage levels held at 1992 levels to ■ simulate effect of no improvements to reduce leakage levels. If existing leakage above 14.5 1/prop/hr constrained to this figure at reduction rnte of 0.5 1/prop/hr. 10 Leakage targets achieved affecting n ■ Leakage reduction in total treated water losses to 11 1/prop/hr. Rate of reduction 0.5 1/prop/hr. 11 Leakage targets achieved affecting a ■ reduction in total treated water losses to-10 l/prop/hr. Rate of reduction 1.0 1/prop/hr. WRWRS.REP/75F/27 June 1994 Page 35 The scenarios which can be built.up using these assumptions are as follows:- * Low demand scenario This can be defined as the line describing the set of assumptions which indicate the minimum increase (or even decrease) in demand in 2021. It forms the lower boundary of the demand envelope. Medium demand scenario The medium scenario can be defined as the line which shows a modest set of assumptions on per capita consumption growth, metering and leakage. It is important to note that this line is not regarded as a preferred or most likely line relative to the other two scenarios. High demand scenario This scenario is defined as the line which describes the maximum feasible increase in demand. This line forms the upper boundary to the demand envelope 4.3.2 Assumptions underlying demand scenarios 4.3.2.1 Population data Population figures to 2021 are based on the 1993 Returns to OFWAT for Dwr Cymru and WEDWC. CWC data is taken from the NRA’s National Water Resources Strategy. Figures for 1996 to 2011 are linearly interpolated from Returns and figures for 2016 to 2021 are linearly extrapolated from the Returns. Any population forecast data from whatever source can only represent a view of the most likely way forward at the time of preparation. It is not possible to make exact predictions of population growth and how this will affect future demography. Nevertheless, the use of company and NRA data, which is based on the 1991 census, is believed to represent the best available data extending to 2021. 4.3.2.2 Occupancy rates Occupancy rates have been derived from population and household numbers data in OFWAT Returns. 4.3.2.3 Per capita consumption (PCC) Figures for 1992 are taken from OFWAT Cost of Water Delivered 1992-93 (Ref 17). Metered household consumption is assumed to be 10% less than in unmetered households in existing metered properties. Preliminary information from metering trials in the Isle of Wight have indicated that the installation of meters in domestic properties results in an average reduction »n household consumption of 20%, of which 10% can be attributed to lower customer demand, and the remainder to reduced supply pipe leakage which is identified upon installation of meters. However, as a result of consultation and in recognition of the need to consider that this 10% reduction may not be a sustained effect, a 10% reduction in PCC upon metering is not invoked under the high forecast. For the base year total treated water losses is derived as the residual of distribution input after the other components have been accounted tor. In subsequent years total treated water losses is directly calculated on the basis of total treated water losses per property (‘night flows’). A saving on the night flow figure is therefore assumed for existing and new metered properties. The level of this saving is 1.5 1/prop/hr. Page 36 WRWRS.REP/75F/27 June 1994 The growth factors used are derived from Binnie and Herrington (Ref 18) in all but the high demand scenario. The data given for 1991, 2011, and 2021 given are described by a straight line, the equation of which has been used to calculate annual compound percentage growth factors. In the case of the high demand scenario a growth rate of 1 % compound has been used to indicate the upper limit of PCC growth suggested by Binnie and Herrington. Under the low and medium demand scenarios the rate of growth in PCC is constrained to a maximum of 180 1/hd/day. This figure reflects a proposed upper limit fro consumption at 2021 based on a component of use analysis of households in the south and south east of England. It is recognised that this limit may be artificial, but given the uncertainty in initial PCC figures at the start of the planning period, this limit is believed to be appropriate. For similar reasons, under the high demand scenario PCC growth is constrained to an upper limit of 189 l/hd/day. 4.3.2.4 Domestic metering Within the three demand scenarios a number of assumptions have been made about future household numbers and levels of domestic metering. These are detailed in Tables 4.2-4.4. County Structure Plans (CSPs) contain information about future housing development. Unfortunately, the CSPs covering the Welsh Region have planning horizons ending around 2001 and are due for renewal in the near future. Therefore, future household numbers have been taken from the October 1993 OFWAT returns. 4.3.2.5 Growth of non-household demand Under the high and medium demand scenarios unmetered non-household demand are considered to grow at an annual rate of 0.75% and 0.5% respectively. This is intended to indicate the upper extent of any growth in these components as well as the effect of modest growth. Zero growth under the low demand scenario is intended to show the effect of increased charges for discharges. 4.3.2.6 Leakage Leakage targets incorporated in the demand scenarios have been based on those used in the national strategy, and are as follows: * Low demand Dwr Cymru Target of 10 l/prop/hr (reduced at 1 1/prop/hr/yr); CWC/WEDWC Reduction of 0.051/prop/hr/yr; * Medium demand Dwr Cymru Target of 11 1/prop/hr (reduced at 0.5 l/prop/hr/yr); CWC/WEDWC Reduction of 0.025 1/prop/hr/yr; High demand Dwr Cymru Target of 14.5 1/prop/hr (reduced at 1.0 1/prop/hr/yr); CWC/WEDWC 1992 leakage levels. Both CWC and WEDWC both already have leakage levels below the target levels used in the national strategy. Under all demand scenarios any metered properties have their leakage target reduced by 1.5 1/prop/hr. WRWRS.REP/75F/27 June 1994 Page 37 Table 4.2 Dwr Cymru PWS demand forecast household numbers assumptions mmmMmmmrnrnm MM ^i;aooBi: | l | f l I S P § IIMI l l i i l f c Population [A] OFWAT return 2758000 2781200 2817000 2849000 2867000 2877000 2887000 Occupancy rate [Bl_ A/E 2.65 2.61 2.56 2.51 2.45 2.39 2.33 No. of metered households _ [c i_ OFWAT retirn 26200 31000 33500 36000 38500 41000 43500 No. of unmetered households PI OFWAT retirn 1014000 1033000 1065500 1098000 1130500 1163000 1195500 Total No. households PI C + 0 1040200 1064000 1099000 1134000 1169000 1204000 1239000 No. old prod’s connected to meters fFl C{96}-C {92} ETC 4800 2500 2500 2500 2500 2500 New prop's in 5 vr period 101 E{96>-E{92} ETC 23800 35000 35000 35000 35000 35000 i l l l l i IlliliJ lliillili l t l » i m i i l i l l I l i l S l t HH HH No. metered households _ IH J . C + SUM(G) 26200 54800 92300 129800 167300 204800 242300 No. unmetered households E-H 1014000 1009200 1006700 1004200 1001700 999200 996700 ■k 1 % ? " ' m&KBM 5 ' ' l i i i i i i i l f l l l i l l t l l i l l l i l l i l l l l l l No. metered households WJ C+suM(G) from 2006 26200 31000 33500 36000 73500 111000 148500 No. unmetered households [K] £-J 1014000 1033000 1065500 1098000 1095500 1093000 1090500 w m * ■ 'i8S&"r 2QW-: '£8Qa$g pgaa*®&; i l l ■ a : • l i i i i J l ■ f l i t t l i i i No. metered households ILl c 26200 31000 33500 36000 38500 41000 43500 No. unmetered households |M1 D 1014000 1033000 1065500 1098000 1130500 1163000 1195500 Table 4.3 WEDWC PWS demand forecast household numbers assumptions i j l l l l l p l w & a a m w & m m MacHSS; m m m N H i p i m # : m m m ! M H l M i l l Population . [A] OFWAT return 148020 149440 151310 152870 154040 154300 154560 Occupancy rate [B] a /£ 2.67 2.64 2.59 2.55 2.51 2.47 2.43 No. of metered households [C] OFWAT retun 2770 4044 5974 7724 9300 10500 11700 No. of unmetered households [D] OFWAT retirn 52610 52534 52404 52274 52144 52014 51884 Total No. households IE1 C+D 55380 56578 58378 59998 61444 62514 63584 No. old prop's connected to meters (FI C{96>-C(92> ETC 1274 1930 1750 1576 1200 1200 New prop’s in 5 vr period IG1 E{96> —E{92> FTC 1198 1800 1620 1446 1070 1070 iOWFOP6 No. metered households m H -SUM(G) FROM 2006 2770 4044 5974 7724 7854 7984 8114 No. unmetered households M , E-J 52610 52534 52404 52274 53590 54530 55470 ...... •; 'iO b s t- : m s m k ssao w ; : '20GB s m v i $ m t B - ' 2 S X t\ ^ ^ : ^ ^ ^ i l i i l l | | | | No. metered households ILl H-SUM(G) FROM 1996 2770 4044 4174 4304 4434 4564 4694 No. unmetered households IM1 E-L 52610 52534 54204 55694 57010 57950 58890 Table 4.4 CWC PWS demand forecast household numbers assumptions dtfcs! d a Va Sou eft ■199? j 199S- : 2001 : .2t»a 2021 Population |A] n r a National Strategy 116760 119790 124740 131270 137790 142595 147400 Occupancy rate [B] A/E 2.88 2.91 2.93 2.99 3.05 3.06 3.08 No. of metered households fc i OFWAT retirn 1330 2270 4120 5970 7820 9670 11520 No. of unmetered households PI OFWAT return 39160 38900 38400 37900 37400 36900 36400 Total No. households IE1 C+D 40490 41170 42520 43870 45220 46570 47920 No. old prop's connected to meters [F] C{96>-C{92} ETC 940 1850 1850 1850 1850 1850 New prop's in 5 yr period [G1 E {96}-E {92}E T C 680 1350 1350 1350 1350 1350 LOW r-OBECASr 1902 . 19B& 2QEH ^ gnpg ‘ 20** , i ' a o ta SQ St\ No. metered households fHl C 1330 2270 4120 5970 7820 9670 11520 No. unmetered ‘ .ouseholds ro D 39160 38900 38400 37900 37400 36900 36400 MEDIUM FORECAST 1-992- 180&S ; ■ 200* _ 2006 ■ : 20** !^ a w e : £021 No. metered households M H-SUM(G) FROM 2006 1330 2270 4120 5970 6470 6970 7470 No. unmetered households (XI E-J 39160 38900 38400 37900 38750 39600 40450 2001 i.&zooe ;v * :■: :;v :£:::£x;: x: :gi :>'.V.- ■: - ■■ ■■ No. metered households IM H-SUM(G) FROM 1996 1330 2270 2770 3270 3770 4270 4770 No. unmetered households [M] E-L 39160 38900 39750 40600 41450 42300 43150 Page 38 C:\JOBS\4432\PWS.WK3\27-Jun-94 43.3 Demand forecasts The PWS demand forecasts for the three water companies, calculated in accordance with the methodology described above, are presented in Tables 4.5-4.7 and Figures 4.1-4.3. The Dwr Cymru forecast ranges from a 4% decrease in demand for potable water under the low scenario to a 19% increase under the high scenario. Non-potable demands increase to 70% of 1992 allocation under the low forecast to 100% of 1992 allocation under the high forecast. The WEDWC forecast ranges from a 12% increase in demand for potable water under the high scenario to a 31% increase under the high scenario. The CWC forecast ranges from a 30% increase in demand for potable water under the high scenario to a 47% increase under the high scenario. Table 4.8 summarises the Region-wide forecast (including exports). Growth in total demand within the Region range from a 2% decrease by 2021 for the low scenario to a 22% increase for the high scenario. The medium growth scenario indicates a regional increase in demands of 6% by 2021 from 1247 Ml/d to 1328 Ml/d. The planning forecasts of the three water companies agree to within 7% of the medium growth scenario forecast. A significant proportion of PWS demand is to meet losses through leakage and therefore estimates of these losses are a key component of the demand forecasts. There is some debate at present on how to assess leakage with differences in approach by the local companies. It is the policy of the NRA to ensure that water companies are doing all they can to reduce leakage down to an economic level before a new resource development is authorised. This appraisal should take into account the environmental costs as well as the purely financial cost of any new scheme. Substantial expenditure would be required to reduce leakage down to the targets assumed in the low demand scenario forecast. However, there would be other considerable benefits arising in terms of improved drinking water quality and overall standard of service to the cunsumer. 4.3.3.1 Peak week demands The OFWAT indicator for raw water availability compares the average daily demand during the peak week with the yield of the sources for each supply zone or company area. This criterion has been used to assess the adequacy of existing raw water sources to meet the low, medium and high growth forecasts for each company during the period 1996 to 2021. Factors of 1.06 and 1.12 have been applied to the calculated average daily demands to estimate peak week demands for Dwr Cymru and CWC & WEDWC respectively, based on information obtained from the water companies. Peak week demand forecasts for the three companies are presented in Table 4.9. Information obtained from Dwr Cymru relating to their own demand forecasts indicates that the Company expects demand growth to be non-uniformly distributed with population growth forecast to be greater in the Northern Division and leakage reduction forecast to be greater in the South-East Division. However, to maintain consistency with the NRA National Water Resoureces Strategy approach, the total peak demand is distributed between supply zones using 1992 supply zone population distribution figures provided by the Company. This assumes direct correlation between supply zone peak demand and population, and no change in the distribution over the planning horizon. Detailed peak week demands for PWS at a supply zone level are provided in Appendix G. WRWRS.REP/75F/27 June 1994 Page 39 Dwr Cymru non-potable demands are included at the same levels as used in the annual average daily demand forecasts. The NWWL abstraction at Chester is assumed to increase from 547 Ml/d to 580 Ml/d in the peak week, but other exports are included as in the average daily demand forecasts. 4.3.4 Projected resources shortfall for PWS For planning purposes there should be a margin between projected average daily demands and available resources to allow for outages and higher than average demand years. In order to identify resources shortfalls the forecast peak week demands have been compared with available resources for each company. Table 4.10 summarises the marginal peak week potable water demands in the Region. Detailed figures at a supply zone level are given in Appendix G. Figures 4.5 - 4.7 show these marginal demands over the period 1996 to 2021. In the case of Dwr Cymru the identified,marginal demands are the summed deficits at a supply zone level, and ignore surpluses in supply areas throughout the planning horizon. For Dwr Cymru there is a resource deficit for all forecast scenarios for the entire planning period ranging from 10 Mid under the low growth scenario to nearly 80 Ml/d for the high growth scenario. Development of resources will be required to improve the reliability of the resource system. In the case of WEDWC under the low growth scenario there are no marginal demands. Under the medium scenario there are marginal demands by 2016 and by 2006 under the high scenario indicating the possible full utilisation of the Company’s abstractions from the River Dee. For CWC there are marginal demands under all forecast scenarios, ranging from 7 Ml/d in 2021 under the low growth scenario to 13 Ml/d under the high growth scenario. The projections illustrate how sensitive the timing of new resource development is to the assumptions made in the demand scenarios. For example, if the assumptions for demand management under the low growth scenario prove accurate, only limited resource development would be required to meet peak demands. Only broad indications of the relative degree of resource shortfall and likely timing of developments can be drawn from this analysis. However, it does emphasise the importance of reviewing demand forecasts regularly and the adoption of a consistent methodology for assessment of resource needs between the NRA and water companies. The yield deficiencies will clearly become more significant if the actual long-term increase in demand is closer to the medium or high forecast than to the low forecast. Page 40 WRWRS.REP/75F/27 June 1994 Table 4.5 Dwr Cymru PWS average demand forecasts w m m m Distribution input 1992 (Mi/d) fa) Input 1038.5 Total metered (Ml/d) [b] - input 231.6 _ _ Unm. non-household (Ml/d) jcj Input 42.6 Weighted av. PCC |d] Input 140 HIM— iiiglliiilillilif lllbiiliSlii ilSl Pooulation lei Input 2758000 2781200 2617000 2849000 2867000 2877000 2887000 PCC suppression (f) Input 0.9 0.9 0.9 0.9 0.9 0.9 0.9 Occupancy rate [a] Input 2.65 2.61 2.56 2.51 2.45 2.39 2.33 PCC unm. growth (%) - Low [pi ] Input 0.64 0.64 0.64 0.64 0.64 0.75 0.75 PCC unm. growth (%) - Mod [p2J Input 0.64 0.64 0.64 0.64 0.64 0.75 0.75 PCC unm. growth (%) - High jp3) Input 1 1 1 1 1 1 1 Unm. non hh growti (%) - Low [q1) Input 0 0 0 0 0 0 0 Unm. non hh growtfi i % ) — Med fq21 Input 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Unm. non hh g row* (%) - Hitfi [q3] Input 0.75 0.75 0.75 0.75 0.75 0.75 0.75 No. metered prop. - Low (r1) Input 26200 54800 92300 129800 167300 204800 242300 No. metered prop. — Med fr21 Input 26200 31000 33500 36000 73500 111000 148500 No. metered prop. - H itfi r3) Input 26200 31000 33500 36000 38500 41000 43500 No. unmetered prop. - Low S1] Input 1014000 1009200 1006700 1004200 1001700 999200 996700 No. unmetered prop. - Med s2j Input 1014000 1033000 1065500 1098000 1095500 1093000 1090500 No. unmetered prop. - High S3) Input 1014000 1033000 1065500 1098000 1130500 1163000 1195500 Unm. night flow (l/pr/hi) - Low 111 Input 18.7 14.7 10.7 10.0 10.0 10.0 10.0 11.0 11.0 Unm. night flow (t/pr/hr) - Med *1 Input 18.7 14.5 12.5 11.0 11.0 Unm. night flew (l/pr/bO - High t31 Input 18.7 16.7 14.7 14.5 14.5 14.5 14.5 ■ M S M : l l l i l Metered households (Ml/d) [hi (dxlxaxrl)/lo~6 8.7 Metered non-households (Ml/d) [j] b - h 222.9 Unmetered households (Ml/d) [k] (dxgxs1)/10'‘6 376.2 Distn less UFW (Ml/d) Ml b + c + k 650.4 UFW (Ml/d) [m] a - I 388.1 Nicftt flow (l/pr/hrt fnl Umx10~6)/(r1+s1))/20 18.7 Non-potable demand (Ml/d) 137.6 w m m m s lm m m m IHfei Unmetered PCC (IAid/day) jaa] (aa” x (1 +(p1/100)) * 5) Note 1 143.6 148.3 153.1 158.0 164.1 170.3 Metered PCC (IMd/datf lab] aax 0.9 129.3 133.4 137.8 142.2 147.7 153.3 Unmetered household (Ml/d) [acj ( g x s l x a a )/1 0 "6 378.3 382.1 385.8 387.9 391.8 395.5 Metered household (Ml/d) [ad) ( g x r l XBb)/10'v6 18.5 31.5 44.9 58.3 72.3 86.5 Unmetered non-household (Ml/d) [ae] (ac x (1 + (q1/100t) "S ) 42.6 42.6 42.6 42.6 42.6 42.6 Metered non-household (Ml/d) (af) (s*"x (1+(q1/100))"5) Note 2 231.6 231.6 231.6 231.6 231.6 231.6 Distn. less UFW (Ml/d) Tag) ac + ad +■ ae + rf 671,0 687,9 704.9 720.4 738.3 756.2 Metered losses (Ml/d) [ah] (20xrt x (tl -1.5)/10 "6) 14.4 16.9 22.1 28.4 34.8 41.2 Unmetered losses (M/d) [aj] (20 xs1 x t1)/10~6 295.8 214.5 200.8 200.3 199.8 199.3 UFW (Ml/d) (<*] eh + ai 310.2 231.4 222.9 228.8 234.7 240.5 TOTAL DISTRIBUTION INPUT (Ml/d) |al] ag + ak 981.2 919.3 927.B 949.1 972.9 996.8 Non—potable demand (M!/d) 137.6 137.S 137.6 137.6 137.6 137.6 m £ d iLiw Fo r e c a s t SOURCE . a o it ■.•■■<201 Unmetered PCC ii/hd/day) [baj |ba,’x(1+(p&100*)''5) Note 1 143.6 148.3 153 if 158.0 164.1 170.3 Metered PCC (l/hd/day) [bb] ba x 0.9 129.3 133.4 137.8 142.2 147.7 153.3 Unmetered household (Ml/d) [be] (g x s2 x ba)/10 " 6 387.2 404.4 421.9 424.2 428.6 432.7 Metered household (Ml/d) |bd) (g x r2x bb)/10 “'6 10.5 11.4 12.4| 25.6 39.2 53.0 Unmetered non-household (Ml/d) [be] (be x (1 +(q2/l00)) A 5} 43.5 44.6 ■ 45.71 46.8 48.0 49.2 Metered non-household (Ml/d) [bf] I b f x d +(q2M0(J)) ~5) Note 2 236.3 242.2 248.31 254.6 261.1 267.6 Distn. less losses (Ml/d) [bg) be + bd + be + bf 677.4 702.7 728 4] 751.2 776.8 802.6 Metered losses (Ml/d) [bh) (20 x r2 x (t2— 1,5)/10 ~ 6) 8.1 7.4 6.8 14.0 21.1 28.2 Unmetered losses (Ml/d) [bj] (20 x s2 x t2)/10~ 6 299.6 266.4 241.6 241.0 240.5 239.9 Total losses (Ml/d) . (bk) bh + bj 307.6 273.7 248.4 255.0 261.6 268.1 TOTAL DISTRIBUTION INPUT (Ml/d) [blj bg + bk 985.0 976.4 976.8 1006.2 1038.3 1070.7 Non-potable demand (Ml/d) 141.2 146.3 151.4| 156.6 161.7 166.8 HKj H f . SOURCE . 1W 6 ' ■ 2001 ; 20 Notes: 1 For 1996 use [d x (1 + (p/100)) ~ 4)) 2 For 1996 use Jj x (1 +(q/lOO)) " 4)) C:\JOBS\4432\PWS.WK3\27-Jun-94 Page 41 Table 4.6 WEDWC PWS average demand forecasts M M N H i Distribution Input 1992 (Ml/d) {a] Input 42.3 Total metered (Ml/d) {bl Input 13.4 Unm. non—household (Mid) (cl Input 0.9 Wel^ttedav. PCC (d) Input 144 P P I P S l s l ® ® w a & m m M M f l N M M M a M f a i i t Population (el Input 146020 149440 151310 152870 154040 154300 154560 PCC suppression |f] Input 0.90 0.90 0.90 0.90 0.90 0.90 0.90 Occupancy rate [g] Input 2.67 2.64 2.59 2.55 2.51 2.47 2.43 PCC unm. growth (%) - Low [ p l| Input 0.64 0.64 0.64 0.64 0.64 0.75 0.75 PCC unm. growth (%) - Med [p2] Input 0.64 0.64 0.64 0.64 0.64 0.75 0.75 PCC unm. growth (%) - Hlah |p3l Input 1.00 1.00 1.00 1.00 1.00 r 1.00 1.00 Unm. non hh growth <%) - Low [ql] Input 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Unm. non hh growth {%) - Med [q2] Input 0.50 0.50 0.50 0.50 0.50 0.50 0.50 Unm. non hh growth (%) - High [q3] Input 0.75 0.75 0.75 0.75 0.75 0.75 0.75 No. metered prop. - Low r1 Input 2770 4044 5974 7724 9300 10500 11700 No. metered prop. - Med r2 Input 2770 4044 5974 7724 7854 7964 8114 No. metered prop. - High [r3] Input 2770 4044 4174 4304 4434 4564 4694 No. unmetered prop. — Low [si ] Input 52610 52534 52404 52274 52144 52014 51884 No. unmetered prop. — Med [s2] Input 52610 52534 52404 52274 53590 54530 55470 No. unmetered prop. - High js3] Input 52610 52534 52404 55694 57010 57950 58890 Unm. nlcfit flow (l/pr/hr) - Low [t1] Input 7.0 6.7 6.5 6.2 6.0 5.7 5.5 Unm. nlcfit flow (l/pr/hr) — Med [12] Input 7.0 6.9 6.8 6.7 6.6 6.5 6.4 Unm. nlfjit flow (l/pr/hr) - High [13] input 7.0 7.0 7.0 7.0 7.0 7.0 7.0 • * 1 1 * ilillli Metered households (Mi/d) |h) ( tJ x lx g x M ) /1 0 ''6 1.0 Metered non -hou se h old s (M id ) [j] b - h 12.5 Unmetered households (Ml/d) [k] (dx gxsi)/i0''6 20.2 Distn less UFW (Ml/d) 111 b + c + k 34.6 UFW (Ml/d) [m] a - 1 7.7 Night flow (l/pr/hr) [n} ((mxl0,'6)/(rl +s1))/20 7.0 . , . 1 | SMSPH m m m m Unmetered PCC (l/hd/dav) laa] faa" x (1 +(pt/iO O )) ''S ) Note 1 147.7 152.5 157.5 162.6 168.7 175.2 Metered PCC (l/hd/day) lab] aa x 0.9 132.9 137.3 141.7 146.3 151.9 157.7 Unmetered household (Ml/d) [ac] (gx si xaa)/lOn6 20.5 20.7 21.0 21.3 21.7 22.1 Metered household (Mid) [ad] (qxrl xab)/10~6 1.4 2.1 2.8 3.4 3.9 4.5 Unmetered non-household (Ml/d) 36] acx(1+(q1/100))-5) 0.9 0.9 0.9 0.9 0.9 0.9 Metered non-household (Ml/d) an faf"x 0 + (ql/l00))~5) Rote 2 13.4 13.4 13.4 13.4 13.4 13.4 Dtstn. less UFW (Mid) lag] ac + ad + ae + at 36.2 37.2 38.1 39.0 40.0 40.9 Metered losses (Ml/d) [ah] (20 x r l x (t1-1.5)/l0~G > 0.4 0.6 0.7 0.8 0.9 0.9 Unmetered losses (M id) [a|] (20 x s i x t ij/ io ^ e 7.1 6.8 6.5 6.2 6.0 5.7 UFW (Mid) fakl ah + ai 7.5 7.4 7.2 7.1 6.9 6.6 TOTAL DISTRIBUTION INPUT (Mid) fall ag + ak 43.7 44.6 45.4 46.1 46.8 47.5 ...... " " SOURCE 1096 2001 2008 . ,55011 201$ 2021 Unmetered PCC (l/hd/day) [ba] (ba"x (1+(p2/100))~5) Note 1 147.7 152.5 157.5 162.6 168.7 175.2 Metered PCC (l/hd/dav) Ibbl ba x 0.9 132.9 137.3 141.7 146.3 151.9 157.7 Unmetered household (Ml/d) [be] (gx s2 x baj/io^e 20.5 20.7 21.0 21.9 22.7 23.6 Metered household (Mid) [bd] (gx r2 x bbJ/IO^e 1.4 2.1 2.8 2.9 3.0 3.1 Unmetered non-household (Ml/d) [be] (be x (l+(q2/l00))~5) 0.9 0.9 1.0 1.0 1.0 1.0 Metered non-household (Ml/d) [bO (bf"x(1+(ce/100))''5) Note 2 13.7 14.1 14.4 14.8 15.1 15.5 Distn. less losses (Ml/d) [bg] be + bd + be + bl 36.5 37.8 39.2 40.5 41.9 43.3 Metered losses (MVd) [bh] (20 x r2 X (t2 — 1,5)/10 ~ 6) 0.4 0.6 0.8 0.8 0.8 0.8 Unmetered losses (M id) [bj] (20 x s2 x t2)/10~6 7.2 7.1 7.0 7.1 7.1 7.1 Total losses (Ml/d) [bk] bh + bj 7.7 7.7 7.8 7.9 7.9 7.9 TOTAL DISTRIBUTION INPUT (Mid) [bl] bq + bk 44.2 45.6 46.9 48.4 49.7 51.2 fJlOH FORECAST ■ SOURCE , ’ -.v ■ n r-a w ix z a t i 2< m w m unmeierea PCC (i/ha/aay) |ca] (ca X (1+(p3/l00))~5) Note i 149.8 157.5 165.5 174.0 182.8 189.0 Metered PCC (l/hd/day) [cb] ea x 0.9 134.9 141.7 149.0 156.6 164.6 170.1 Unmetered household (Ml/d) fee] (gx S3 x ea )/l0 ~ 6 20. a 21.4 23.5 24.9 26.2 27.0 Metered household (Mid) |cd] (g x r3 x cb)/10~ 6 1.4 1.5 1.6 1.7 1.9 1.9 Unmetered non-household (Ml/d) [ce] (ccx (1 +(q3/100)} ^ 5) 0.9 1.0 1.0 1.0 1.1 1.1 Metered non— household (Ml/d) [cf] (C l" x (1 + (tJ3/100))x'5 ) Note 2 13.8 14.4 14.9 15.5 16.1 16.7 Distn. less losses (Ml/d) [eg] cc + cd + ce + cf 37.0 38.2 41.1 43.2 45.2 46.8 Metered losses (Mid) [ch] (20 x r3 X (0-1.5)/10~6) 0.4 0.5 0.5 0.5 0.5 0.5 Unmetered losses (M id) [cj) (20 x s3 x t3)/10~6 7.3 7.3 7.8 8.0 8.1 8.2 Total losses (Ml/d) [ck] ch + cj 7.8 7.8 8.2 8.4 8.6 8.7 TOTAL DISTRIBUTION INPUT (Mid) [cl]. eg + ck 44.8 46.0 49.3 51.6 53.8 55.5 N otes: 1 For 1996 use [d x (1+(p/iOO)) ~4)J 2 For 1996 use [j x (1 + (cyi00))~4)] Page 42 C:\JOBS\4432\PWS.WK3\27 - Jun -94 Table 4.7 CWC PWS average demand forecasts — — Bit ' ■ '■ '-r v ' \ ' HHHKMHI Distribution Input 1992 (Ml/d) fa) Input 20.9) Total metered (Ml/d) fb] Input 6.81 Unm. non-household (Ml/d) fc] Input 0.4 - = - W el^itedav. PCC fd} Input 147 | UMKEQ0ATA' ■ ^ - ■ ’i. I M H 1 Populatbn [e] input 116760 119790 124740 131270 137790 142595 147400 PCC suppressbn [f] Input 0.9 0.9 0.9 0.9 0.9 0.9 0.9 Occupancy rate fg] Input 2.88 2.91 2.93 2.99 3.05 3.06 3.06 PCC unm. growth (%) - Low |p l] Input 0.64 0.64 0.64 0.64 0.64 0.75 0.75 PCC unm. growth (%) - Med [p2] Input 0.64 0.64 0.64 0.64 0.64 0.75 0.75 PCC un m qxowth (%) - Hiqh [p3] Input 1 1 1 1 1 1 1 Unm. non hh growth (%) — Low {q l ] Input 0 0 0 0 0 0 0 Unm. non hh growth (%) - Med [q2] input 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Unm. non hh growth (%) - High [q3] Input 0.75 0.75 0.75 0.75 0.75 0.75 0.75 No. metered prop. - Low r1 Input 1330 2270 4120 5970 7820 9670 11520 No. metered prop. - Med r£ Input 1330 2270 4120 5970 6470 6970 7470 No. metered prop. - High fr3] Input 1330 2270 2770 3270 3770 4270 4770 No. unmetered prop. - Low fsl] Input 39160 38900 3S400 37900 37400 36900 36400 No. unmetered prop. - Med {82] Input 39160 38900 38400 37900 36750 39600 40450 No. unmetered prop. - High Is3l Input 39160 38900 39750 40600 41450 42300 43150 Unm. nlgfit flow (1/pr/hr) - Low [M] Input 6.3 6.1 5.9 5.7 5.5 5.3 5.1 Unm. n iffit flow (l/pr/hr) - Med [12] Input 6.3 6.2 6.1 6.0 5.9 5.8 5.7 Unm. n lfjit flow (l/pr/hr) - High [t3] Input 6.3 6.3 6.3 6.3 6.3 6.3 6.3 wmm wmMmmmmmm; ! ■ Metered households (Ml/d) [h] (d x Ix g x r1 )/1 0 ~ 6 0.5 Metere d non - hous eho Ids (Mid) []] b - h 6.3 Unmetered households (Mid) [k] (dx gxsl)/lOA6 16.6 Distn less UFW (Ml/d) (11 b + c + k 23.8 UFW (Mid) fm] a -1 5.1 Night flow (l/pr/hr) [n] ((m x 10 A6)/(rl -+-sl))/20 6.3 ispipraeiiiiiii ■ ■ l i i l ; i l l Unmetered PCC (IAid/day) [aa] (aa" x (1 +(p l/l0 0 )) ~5) Note 1 150.8 155.7 160.7 165.9 172.3 178.8 Metered PCC (l/hd/day) [ab| aa x 0.9 135.7 140.1 144.7 149.3 155.0 160.9 Unmetered household (Ml/d) [ac] (g x s1 x aa)/10 A 6 17.1 17.5 18.2 18.9 19.5 20.0 Metered household (Ml/d) [ad] (g x r1 x abJ/IO^S 0.9 1.7 2.6 3.6 4.6 5.7 Unmetered non-household (Ml/d) ae] lac x (1+(q1/100)r 5) 0.4 0.4 0.4 0.4 0.4 0.4 Metered non-household (Ml/d) af] af x (1 + (ql/1 00Jp* 5) Note 2 6.8 6.8 6.8 6.8 6.8 6.8 Distn. less UFW (M id) fag] ac + ad + ae + af 25.2 26.4 28.0 29.7 31.2 32.9 Metered losses (M id) [ah] ( 2 0 x rlx (t1 -1 .5 )/1 0 /'6 ) 0.2 0.4 0.5 0.6 0.7 0.8 Unmetered losses (M id) [aj] (20 X S1 Xt1)/10~6 4.8 4.6 4.3 4.1 3.9 3.7 UFW (Mid) fakl ah + a| 5.0 4.9 4.9 4.8 4.7 4.6 TOTAL DISTRIBUTION INPUT (MJ/d) [a!) ag + ak 30.1 31.3 32.8 34.5 35.9 37.5 ...... " $ O M £ . \ \ i s m 'S B ftV .20*6 Unmetered PCC (lAid/day) [ba) (ba" x (1+(p2/100))y'5 ) Note 1 150.8 155.7 160.7 165.9 172.3 178.8 Metered PCC (l/hd/day) rbb] ba x 0.9 135.7 140.1 144.7 149.3 155.0 160.9 Unmetered household (Ml/d) [be] (gx s2 x b a j/io ^ e 17.1 17.5 18.2 19.6 20.9 22.3 Metered household (MVd) [bdj (gxr2 x bb)/10^6 0.9 1.7 2.6 2.9 3.3 3.7 Unmetered non-household (M)/d) (be] (bcx (i+ (q 2 /iro ))^ 5 ) 0.4 0.4 0.4 0.4 0.4 0.4 Metered non-household (Ml/d) fbf| ( b f x 0 + (cfi/l0 0 ))~ 5 l Note 2 7.0 7.2 7.3 7.5 7.7 7.9 Distn. less losses (Ml/d) Jbg] be + bd + be + bf 25.3 26.7 28.5 30.5 32.3 34.3 Metered losses (M id) fbh] (20 X r2 X (t2 — 1,5)/10 A 6) 0.2 0.4 0.5 0.6 0.6 0.6 Unmetered losses (M id) [bj] (20 x s2 x t2)/10 ~ 6 4.9 4.7 4,6 4.6 4.6 4.6 Total losses (Ml/d) [bk] bh + bj 5.1 5.1 5.1 5.2 5.2 5.3 TOTAL DISTRIBUTION INPUT (M id) [bll bq + bk 30.4 31.8 33.6 35.6 37.5 39.6 HJQH FORECAST SOURCE i m 2001. 2ora , 2Qt1 2021 Unmetered PCC (Wid/day) [ca] (ca" X (1+(p3/100))~5) Note 1 153.0 160.8 169.0 177.6 186.7 189.0 Metered PCC (l/hd/day) [cb] ca x 0.9 137.7 144.7 152.1 159.8 168.0 170.1 Unmetered household (Ml/d) [cc] (QX S3xca)/10~6 17.3 18.7 20.5 22.5 24.2 25.1 Metered household (M id) [cd] (g x r3 x cbJ/IO^G 0.9 1.2 1,5 1.6 2 J2 2.5 Unmetered non-household (Mt/d) [ce] (ccx (l+(q3/100))~5) 0.4 0.4 0.4 0.4 0.4 0.4 Metered non-household (Ml/d) [cf] (cfx(1 + (q 3 /1 0 0 ))~ S ) Note 2 7.0 7.3 7.6 7.9 8.2 8.5 Distn. less losses (Ml/d) [eg] cc + cd + ce + cf 25.6 27.6 30.0 32.6 35.0 36.5 Metered tosses (Mid) [ch] (20 x r3 x (0 -1 .5 )/1 0 ~ 6 ) 0.2 0.3 0.3 0.4 0.4 0.5 Unmetered losses (M id) [c]] (20 x S3 x I3 )/1 0 ~ 6 4.9 5.0 5,1 5.3 5.4 5.5 Total losses (Ml/d) (ck] ch + q 5.1 5.3 5,5 5.6 5.8 5.9 TOTAL DISTRIBUTION INPUT (MVd) [cl] eg + ck 30.8 32.9 35.4 38.2 40.7 42.5 Notes: 1 For 1996 use [dx (1 +(p/100)) ~4)] 2 For 1996 use U x (1+(cyi00))~4)] C:\JOBS\4432\PWS.WK3\27-Jun-94 Page 43 Table 4.8 PWS average demand forecasts for the Region (including exports) |||^g |T A ',-: : ' r SmmtM wmm stw o a s : wmommmm i M M l i mmem Dwr Cymru Potable 1291 1039 Dwr Cymru Non-Potable 196 138 DWR CYMRU TOTAL 1487 1176 WEDWC 54 42 CWC 35 29 WELSH COMPANIES TOTAL 1575 1247 S.T. Elan Valley 1 335 320 S.T. Lydbrook 2 36 30 NW Water - Chester3 650 547 NW Water - Llangollen 47 37 TOTAL INCLUDING EXPORTS 2643 2181 m i 1 ' 9 NHNNN-:* v ifli i£§i:9$e - 'mm mmm ; i i 2 M mmm mmm Dwr Cymru Potable 981 919 928 949 973 997 Dwr Cymru N on-Potable 138 138 138 138 138 138 DWR CYMRU TOTAL 1119 1057 1065 1087 1111 1134 WEDWC 44 45 45 46 47 48 CWC 30 31 33 34 36 38 WELSH COMPANIES TOTAL 1193 1133 1144 1167 1193 1219 S.T. Elan V a lley' 335 335 335 335 335 335 S.T. Lydbrook 2 31 32 33 34 35 36 NW Water — Chester 3 547 547 547 547 547 547 NW Water - Llangollen 37 37 37 37 37 37 TOTAL INCLUDING EXPORTS 2143 2084 2096 2120 2147 2174 IfPltMMFORECAST ••• ^ * H H i H i ‘ .....■...... •..... r*\ = § ! $ $ & mrnmm■289$$w m m Dwr Cymru Potable 985 976 977 1006 1038 1071 Dwr Cymru Non-Potable 141 146 151 157 162 167 DWR CYMRU TOTAL 1126 1123 1128 1163 1200 1238 WEDWC 44 46 47 48 50 51 CWC 30 32 34 36 38 40 WELSH COMPANIES TOTAL 1201 1200 1209 1247 1287 1328 S.T. Elan Valley 1 335 335 335 335 335 335 S.T. Lydbrook 2 31 32 33 34 35 36 NW Water - Chester 3 547 547 547 547 547 547 NW Water — Llangollen 37 37 37 37 37 37 TOTAL INCLUDING EXPORTS 2151 2151 2161 2200 2241 2283 HIGH FORECAST is Deroantf « *> / 1 $$$ 20fn 2006 aait 20*6 ; 2021 Dwr Cymru Potable 1039 1044 1089 1137 1186 1236 Dwr Cymru Non—Potable 145 155 165 176 186 196 DWR CYMRU TOTAL 1184 1199 1254 1312 1372 1432 WEDWC 45 46 49 52 54 56 CWC 31 33 35 38 41 42 WELSH COMPANIES TOTAL 1260 1278 1339 1402 1466 1530 S.T. Elan Valley 1 335 335 335 335 335 335 S.T. Lydbrook2 31 32 33 34 35 36 NW Water - Chester 3 547 547 547 547 547 547 NW Water - Llangollen 37 37 37 37 37 37 TOTAL INCLUDING EXPORTS . 2210 2229 2291 2355 2420 2485 Notes 1 Excluding 5 Ml/d yield included in DC potable demand 2 Excluding 9 Ml/d yield included in DC potable demand '3 Excluding 36 Ml/d reserved for DC non-potable demand of 27 Ml/d Page 44 C:\JOBS\4432\PWS.WK3\27-Jun-94 „ Low forecast Medium forecast^ High forecast excludes non — potable demand Figure 4.2 WEDWC PWS demand forecasts Average daily demand 1992 1996 2001 2006 2011 2016 2021 Low Forecast Medium Forecast High Forecast C:\JOBS\4432\PWS. WK3\27 - Jun - 94 Page 45 Figure 4.3 CWC PWS demand forecasts ______Average daily demand ______ _*_Low Forecast Medium Forecast^- High Forecast Page 46 C:\JOBS\4432\PWS.WK3\27-Jun-94 Table 4.9 PWS peak week demand forecasts for the Region ...- i& s m m ' y i f c : r i m i m m i m wm $m s i i S M DC South East drv.(CUA) 1221318 543 487 461 432 436 446 457 468 DC South East div.(N) 185603 104 74 70 66 66 68 69 71 DC South West drv. 864269 409 345 326 305 308 315 323 331 DC Northern dtv.(W) 174237 97 70 66 62 62 64 65 67 DC Northern div.(E) 312573 138 125 118 110 111 114 117 120 Dwr Cymru potable total 2758000 1291 1101 1040 974 984 1006 1031 1057 Dwr Cymru non-potable total 196 138 138 138 138 138 138 138 WEDWC 148020 54 47 49 50 51 52 52 53 CWC 107100 35 32 34 35 37 39 40 42 WELSH COMPANIES TOTAL 3013120 1575 1318 1260 1197 1209 1234 1262 1289 S.T. Elan Valley 335 320 335 335 335 335 335 335 S.fT LydrooK 36 30 31 32 33 34 35 36 NW Water-Chester 650 580 580 580 580 580 580 580 NW Water-Llangollen 47 37 37 37 37 37 37 37 TOTAL INCLUDING EXPORTS 2643 2285 2243 2181 2194 2220 2249 2277 m w m m m m m M i M m m tm w m m m mmm m M m :!£§§${& m h DC South East div.(CUA) 1221318 543 487 462 458 458 472 487 503 DC South East div.(N) 185603 104 74 70 70 70 72 74 76 DC South W est div. 864269 409 345 327 324 324 334 345 356 DC Northern div, (W) 174237 97 70 66 65 65 67 70 72 DC Northern div.(E) 312573 138 125 118 117 117 121 125 129 Dwr Cymru potable total 2758000 1291 1101 1044 1035 1035 1067 1101 1135 Dwr Cymru non-potable total 196 138 139 144 149 154 159 164 WEDWC 146020 54 47 50 51 53 54 56 57 CWC 107100 35 32 34 36 38 40 42 44 WELSH COMPANIES TOTAL 3013120 1575 1318 1267 1265 1274 1314 1357 1400 S.T. Elan Valley 335 320 335 335 335 335 335 335 S.T. LydrooK 36 30 31 32 33 34 35 36 NW Water-Chester 650 580 580 580 560 580 580 580 NW Water—Llangollen 47 37 37 37 37 37 37 37 TOTAL INCLUDING EXPORTS 2643 2285 2250 2249 2259 2300 2344 2388 m 1 * h ig h foaecA&t ■ M w m m n & i i i s i g H A mmm HP m h l i M A ; M ® ! i DC South East div.(CUA) 1221318 543 487 488 490 511 534 557 580 DC South East div.(N) 185603 104 74 74 74 78 81 85 88 DC South West div. 864269 409 345 345 347 362 378 394 411 DC Northern div.(W) 174237 97 70 70 70 73 76 79 83 DC Northern div.(E) 312573 133 125 125 125 131 137 142 148 Dwr Cymru potable total 2758000 1291 1101 1102 1106 1154 1205 1257 1310 Dwr Cymru non-potable total 196 138 145 155 165 176 186 196 WEDWC 148020 54 47 50 52 55 58 60 62 CWC 107100 35 32 34 37 40 43 46 48 WELSH COMPANIES TOTAL 3013120 1575 1318 1332 1350 1415 1481 1549 1616 S.T. Elan Valley 335 320 335 335 335 335 335 335 S.T. Lydrook 36 30 31 32 33 34 35 36 NW Water-*Chester 650 580 580 580 580 580 580 580 NW Water—Llangollen 47 37 37 37 37 37 37 37 TOTAL INCLUDING EXPORTS 2643 2285 2315 2334 2400 2467 2536 2604 C:\JOBS\4432\PWS.WK3\27-Jun-94 Pago 47 Tab!e4.10 PWS peak week marginal demands for the Region ■■ ' ■ w-\ < ■ v ' v' Mai^WiEpnimnci'' (Ml / O. ,71996 ■: ' 2001: |p*'.'2011 i Dwr Cymru S.E. Division 0.1 0.0 0.0 0.0 0.1 0.2 Dwr Cymru S.W. Division 8.7 7.1 7.3 7.9 8.5 9.1 Dwr Cymru N(W) Division 0.0 0.0 0.0 0.0 0.0 0.0 Dwr Cymru N(E) Division 0.1 0.0 0.0 0.0 0.1 0.1 WEDWC 0.0 0.0 0.0 0.0 0.0 0.0 CWC 0.0 0.5 2.2 4.0 5.6 7.4 REGIONAL TOTAL 8.9 7.6 9.5 11.9 14.3 16.8 m m m m m jpcast - '. ^ M arginal "Demand" (M l * * llllllM l§ ^ illl * 'v 4 6 $ f 111112001*: ■ - 2006' >- J £QT* ^ - ^ m m Dwr Cymru S.E. Division 0.16 0.13 0.13 0.28 0.52 0.77 Dwr Cymru S.W. Division 8.8 8.5 8.6 9.5 11.8 14.1 Dwr Cymru N(W) Division 0.0 0.0 0.0 0.0 0.0 0.0 Dwr Cymru N(E) Division 0.1 0.1 0.1 0.1 0.2 0.2 WEDWC 0.0 0.0 0.0 0.4 1.9 3.5 CWC 0.0 1.0 3.1 5.3 7.4 9.7 REGIONAL TOTAL 9.0 9.8 11.8 15.6 21.8 28.3 ;Hl Page 48 C:\J0BS\4432\PWS.WK3\27-Jun-94 :JB\42PSW32-u 94 - C:\JOBS\4432\PWS.WK3\27-Jun Total Demand (Ml/d) Total Demand (Ml/d) Total Demand (Ml/d) C O DWC Z ot Dv( ) (E Div North C D HZ] C W ED W O C CW 3 E OOi £ 2 CW C O W ED W C C W ED W O C CW 2 £ Figure 4.6 PWS marginal demands — medium growth forecast growth — medium demands marginal PWS 4.6 Figure Figure 4.5 PWS marginal demands - low growth forecast growth low - demands marginal PWS 4.5 Figure Figure 4.7 PWS marginal demands - high growth forecast growth high - demands marginal PWS 4.7 Figure DC S.E.Division S.E.Division DC C C]WE C W ED W CZ] C CW 3 C A ^ DC S.W. Division Division S.W. DC EZJ ?/ \ /4 /? X J Z D ot Dv( ) (E Div North DC D ot Dv( ) (E Div North DC DC North Division (W ) ) (W Division North DC Page 4.4 FUTURE DEMANDS FOR INDUSTRY AND AGRICULTURE Forecasts have been made of gross demands for industry and agriculture for the period 1996 to 2021. Where practical these forecasts have been made at a sub-catchment level, otherwise forecasts have been made at a Regional level and sub-catchment figures have been estimated from the distribution of licensed quantity in 1993. Forecasts are based on a range of sources including 1981 to 1991 trends, consultation with interested parties (see Appendix I for a list of organisations contacted), and available published information. The historic demands are included for completeness. Forecasts for the Region are presented in Figures 4.8 - 4.12. Detailed forecasts of estimated gross and net demands at a sub-catchment level are presented in Appendix H. 4.4.1 Power generation 4AAA Hydroelectric power (HEP) Between 1981 and 1992 there has been a 3% increase in licensed quantity (excluding the three recirculation schemes), with actual abstractions amounting to 50% - 70% of licensed quantity. There are opportunities for new HEP schemes within the Region both at existing impoundment reservoirs and new low head installations at river sites. In order to assess the likely future demands for direct abstraction for power generation, the NRA invited all power companies currently operating to submit details of how and where they saw demand increasing in the next 30 years. Nearly 50% of companies responded. The development proposals identified in the Welsh Region were: * Competing proposals for a pumped storage scheme on the Afon Goedol at Ffestiniog (in the Glaslyn sub-catchment) from the National Grid Company and Norweb; * A proposal for a conventional HEP scheme from Powergen on the River Dee, below the tidal limit, at Connah’s Castle. This would not have a significant impact on the Region’s water resources. Dwr Cymru holds a licence at Llyn Celyn to release 373 Ml/d (averaged over 365 days) for power generation. The Company are presently preparing proposals for the installation of an HEP station at Llyn Brianne (in the Upper Tywi sub-catchment) and an extension of the HEP installation at the lowest of the Elan Valley dams (in the Upper Wye sub-catchment). For the purposes of this study it is assumed that Dwr Cymru will seek licences of 340 Ml/d at Llyn Brianne (roughly the mean annual flow passing the dam), and 300 Ml/d at Caban Coch.the lowest of the Elan Valley dams (roughly the mean annual flow remaining in the Elan after the major abstraction of 341 Ml/d has been taken by STWP). Dwr Cymru also has HEP generators installed on the compensation outlets from a number of their impounding reservoirs, but none of these are licensed because water is not released solely to generate power. Dwr Cymru recently commissioned consultants to undertake a feasibility study to assess the potential for HEP generation at eight sites in the Company’s South Eastern Division. Preliminary findings indicate that three to five of the sites may be suitable, but this depends on overcoming any adverse environmental impacts. Page 50 WRWRS.REP/75F/27 June 1994 At a regional level the NRA expects to receive licence applications for at least a further 10 schemes in the near future, two thirds of these being in the Glaslyn sub-catchment. Based on the above information it is assumed that 13 HEP schemes will be developed under a low growth scenario as follows: Conwy sub-catchment One 200 Ml/d scheme by 1996; Upper Wye sub-catchment One 300 Ml/d scheme by 1996; Upper Tywi sub-catchment One 340 Ml/d scheme by 1996; Gwrfai sub-catchment One 100 Ml/d scheme by 2001, one 100 Ml/d scheme by 2006; Glaslyn sub-catchment Three 100 Ml/d schemes by 1996, three 100 Ml/d schemes by 2001, two 100 Ml/d schemes by 2006. Current demand from existing licences is assumed to be 70% of licensed quantity. Under the high growth scenario it is assumed that 20 HEP schemes will be developed as follows: Conwy sub-catchment One 200 Ml/d scheme by 1996; Upper Wye sub-catchment One 300 Ml/d scheme by 1996; Upper Tywi sub-catchment One 340 Ml/d scheme by 1996; Gwrfai sub-catchment One 100 Ml/d scheme by 1996, two 100 Ml/d scheme by 2001, one 100 Ml/d by 2006; Glaslyn sub-catchment Four 100 Ml/d schemes by 1996, three 100 Ml/d schemes by 2001, two 100 Ml/d by 2006; Dwyfor sub-catchment One 100 Ml/d scheme by 1996, one 100 Ml/d schemes by 2001. two 100 Mi/d schemes by 2006. Again, current demand from existing licences is assumed to be 70% of licensed quantity. The low and high growth forecasts are presented in Figure 4.8. Overall a growth ranging rom 280% to 350% by 2021 in gross demand is forecast. However, as HEP is a non consumptive use of water this growth does not significantly affect the water resources of the Region. The NRA is experiencing difficulties persuading applicants to accept and adhere to the conditions under which the NRA is prepared to issue a new licence. It is essential, among other considerations, that future licences should only be issued subject to the condition that future additional upstream consumptive abstractions may be licensed which may adversely affect the number of units generated and that no financial compensation would then be available. In practice there are unlikely to be many cases where a loss of income would be experienced in these circumstances, because most of the new HEP schemes are likely to draw their water from the upper reaches of rivers. 4.4.1.2 Electricity generationcooling water (non-evaporative cooling water) Cooling water is a minor demand on resources, with only one licensed abstraction from non- tidal waters. Demand decreased by 60% between 1981 and 1991. Virtually all water used for non-evaporative cooling is returned to the river. No new licences are envisaged in this category of use, and therefore no forecast is made. However, it should be noted that a single large new licence could dramatically change the situation. WRWRS.REP/75F/27 June 1994 Page 51 4.4.2 Industry With the decline in traditional heavy industries demand for water by this sector has reduced from 675 Ml/d to 340 Ml/d between 1981 and 1991. Future trends are particularly difficult to forecast but it is probably reasonable to assume there will not be a dramatic upturn in demand. There is provision in the Dwr Cymru forecasts for provision of water to industrial users. The County Structure Plans do not reveal any plans for large scale industrial development in the Region, but many of these are due for renewal in the near future. Therefore, for the high growth scenario demand is assumed to remain at current levels and a 5% per annum decline is taken as the low growth scenario. The forecasts are presented in Figure 4.9. 4.4.3 Agriculture 4.4.3.1 Spray irrigation Estimates of future demand have been based on a recent R&D project commissioned by the NRA (Ref 19), supplemented by historic abstractions data for the Region. The project produced forecasts of irrigation water demands for England and Wales over the horizon 1996 to 2021, using 1990 as the baseline year (selected as representing a design ‘dry year’). Forecasts took account of various factors including cropping patterns, future commodity price levels, irrigation economics and informed opinion under a range of alternative agricultural policy scenarios (ranging from extreme protectionism to agriculture to complete trade liberalism). Under the expected agricultural policy scenario, which relates to the current policy regime introduced in 1992/93 involving a reform of the Common Agricultural Policy and partial acceptance of GATT, the ‘most likely* forecast is a growth in demand for irrigation water of 1.7% per annum from 1996 to 2001 and 1% per annum from 2001 to 2021. This will be due to an expansion in root crop and vegetable irrigated area, partially offset by a decline in grass and cereal irrigated area. The confidence of prediction reduces with time into the future, with forecasts beyond 2001 no better than speculative. Ref 19 also details forecasts of irrigation demand in NRA Regions, using 1992 crop areas and 1990 fractions of crop irrigated and depths of water applied calculated from MAFF data. The derived growth rates are different to those given above, reflecting the different crop mixtures and different starting points. The report highlights the discrepancy between MAFF-based data and NRA abstraction data for 1990, with considerable differences at a Regional level. The forecast demand for 1991 using the MAFF-based data is 3954 Ml, compared with an estimated actual abstraction of 2067 Ml from licence returns. 1991 and 1992, whilst being drier than average years, were not a period of severe drought in the Welsh Region as they were in south-eastern England. However, returns for 1991 and 1992 do indicate that abstraction in 1992 was about 50% greater than in 1991. High and low growth forecasts of spray irrigation demand for this study have therefore been calculated using the growth rates derived for the Region in Ref 19 with 1991 demand data from Chapter 3 of this report as the baseline. Under the low growth scenario demand increases at about 2% per annum between 1996 and 2001 and at 1.4% per annum from 2001 to 2021. Under the high growth scenario the same growth rates are used but demands are set at 50% above the low growth forecast to simulate drought year demands. The forecasts are presented in Figure 4.10. Page 52 WRWRS. REP/75F/27 June 1994 4.4.3.2 General agriculture Demand increased at about 1.5% per annum between 1981 and 1991. However, discussions with representatives of MAFF and the NFU indicate that demand is unlikely to rise above current levels. A low growth forecast of no growth and a high forecast of 0.5% per annum are assumed. The forecasts are presented in Figure 4.U. 4.4.4 Amenity/Conservation Demand for water for amenity or conservation purposes increased sharply from 2 Ml/d to nearly 30 Ml/d between 1981 and 1991, principally due to a single new licence. Discussions with NRA staff indicate demand is expected to remain static. Therefore growth rates of 0.25% per annum and 0.75% per annum have been assumed for the low and high forecasts respectively, shown in Figure 4.12. 4.5 PROJECTED RESOURCES SHORTFALL FOR PRIVATE DEMANDS It can be seen from Figures 4.8 - 4.12 that the only private demands forecast to increase significantly between 1991 and 2021 are spray irrigation and HEP. Other demands are expected to remain at current levels or decrease. In the case of spray irrigation demand is forecast to increase by as much as 140% of 1991 demand by 2021, although gross demand in 2021 is forecast to be lower than the current licensed quantity. This large increase would have a significant impact on resources - spray irrigation is nearly totally consumptive and demands are not uniformly distributed regionally but are concentrated in a few sub-catchments. A number of sub-catchments in the Wye are already subject to an embargo on new licences for spray irrigation because of a lack of resources to meet this demand. Many iicences contain the restriction that water can only be taken when flows in the river at some control point exceed a threshold figure. The forecast makes no allowance to alleviate these factors which already significantly curtail private demands. HEP also sees a large growth over the planning horizon. HEP is a non-consumptive use of water and this increase in demand should not adversely impact on the water resources of the Region as long as certain issues associated with non-consumptive uses (risk of derogation of existing licences, operational impact on fisheries and water quality) are taken into account. This is considered further in Section 6. WRWRS.REP/75F/27 June 1994 Page 53 Figure 4.8 Power generation: HEP average demand forecast High growth ^ Lowgrowth Forecast scenario Gross demand (Ml/d) 1981 19861 1991 1996 2001 2006 2011 2016 2021 H ig h - 94772 " 7sg:o j “ T52672 3203.9 3903.9 ~?3tT3'.9 4303.9 SZOtt “ *303.? Low 947.2 769.0 1626.2 2903.9 3303.9 3603.9 3603.9 3603.9 3603.9 Page 54 c:\jobs\4432\private.wk1\27-Jun-94 Figure 4.9 Industrial average demand forecast 1 1 0 0 1000 900 | 800 700 "Do | 600 1500 400 300 200 1981 1986 1991 1996 2001 2006 2011 2016 2021 ^ High growth + Low growth Forecast scenario Gross demand (Ml/d) 1981 1986 1991 1996 2001 2006 2011 I 2016 2021 High - Sialic . 67572 603.4 ■' M 8 3*0.8 340.8 340.8 340.81 340.8 340.8 Low - 5%/yr decline 675.2 603.4 340.8 323.8 306.7 289.7 272.6 255.6 238.6 c:\jobs\4432\private.wk1\27-Jun-94 Page 55 Figure 4.10 Spray irrigation average demand forecast High growth ^ Low growth Forecast scenario Gross actual demand (Ml/d) 1981 19861 1991 1996 2001 I 2006 2011 2016 2021 High - Drought year "3.01 '4.B5"T 5.66 930' 10.58T 11.49 12.36 13.21 14.01 baseline Low - Average year 3.01 4.86 5.66 6.34 7.05 7.66 8.24 8.81 9.34 baseline Page 56 c:\jobs\4432\private.wk1\27 -J u n -9 4 Figure 4.11 General agriculture average demand forecast High growth ^ Low growth Forecast scenario Gross demand (Ml/d) 1981 1986 1991 19961 2001 20061 2011 | 2016 2021 High - 0.50%/yr growth 11.0 11.2 12.8 13.f I 13.4 ' 13.71 14.1 I 14.4 14.7 Low - static 11.0 11.2 12.8 12.8 12.8 12.8 12.8 12.8 128 c:\jobs\4432\private.wk1\27-Jun-94 Page 57 Figure 4.12 Amenity/Conservation average demand forecast Q ■■■ t______i______i______i______i______i______|______i_ 1981 1986 1991 1996 2001 2006 2011 2016 2021 High growth ^ Low growth For ecast scenario Gross demand (Ml/d) 1981 1986 1991 1996 2001 2006 2011 2016 2021 High - 0.75%/yr growth TT 1.9 28.7 29.8 " 30!5" 31.9 33.0 34.1 35.2 Low - 0.25%/yr growth 1.2 1.9 28.7 29.1 29.4 29.8 30.1 30.5 30.9 Page 58 c:\jobs\4432\private.wk1\27-Jun-94 4.6 ENVIRONMENTAL DEFICITS The formation of the NRA in 1989 coincided with a series of dry years. The lack of rainfall during 1988 to 1992 was particularly acute in the South and South-East of England but all Regions experienced low rainfall, especially in 1989 and 1990. The drought caused a widespread reduction in river flows and groundwater levels which, in certain locations, was compounded by overabstraction. Most of these abstractions were Licences of Right authorised under the Water Resources Act 1963. This gave existing abstractors the right to a licence regardless of any environmental implications. 4.6.1 Alleviation of low flows (ALF) The NRA, with its mandate as the guardian of the water environment, saw the alleviation of these low flow rivers as one of its top priorities. As a first step it identified 40 sites throughout England and Wales where abstractions were perceived to be affecting flows. Seven such rivers are in the Welsh Region: four in the Wye catchment on the rivers Gamber, Garren, Frome and Monnow, two in the Dee catchment on the Afon Clywedog and Afon Alyn, and one on Anglesey on the Afon Cefni. The seven sites have been assessed using a methodology developed by the NRA in 1992 to appraise low flow sites nationally in a consistent manner. The methodology takes account of hydrological conditions, abstractions, ecology, amenity and public perception, leading to identification of the severity of the problem and the reliability of the data used (Ref 20). Many of the sites were originally identified on the basis of public perception rather than firm evidence, and have been shown to be natural or resulting from causes unrelated to abstraction. Table 4.11 details the low flow sites in the Region, together with the current status of investigations. It should he noted that rivers whose low flows in recent summers have been shown to be due to natural, rather than artificial, causes are not listed as the NRA does not believe it is a valid objective to sustain flows above their ‘natural* values. In each case detailed investigation and assessment of worthwhileness will be necessary before amelioration can be undertaken. Table 4.11 also includes six sites which NRA Welsh Region has identified for further investigation in the process of formulating Catchment Management Plans. As the NRA completes more CMPs further sites may be identified. 4.6.1.1 Afon Clywedog In the case of the Afon Clywedog site low flows have been shown to be exacerbated by PWS abstraction at WEDWC’s sources at Minera (Licence no. 67/07/035). Much of the catchment geology is Carboniferous Limestone and the river loses water naturally through swallow holes in the river bed into the underlying limestone. Historic metalliferous mining activities, with associated drainage adits, have exacerbated this natural phenomenon. However, this water is discharged from adits a little further downstream. WEDWC has utilised some of the mine drainage system for PWS. This has further added to the loss of water from the river. When abstractions take place, the discharge from the adits is reduced. WRWRS. REP/75F/27 June 1994 Page 59 Table 4.11 Low flow problem sites in Welsh Region River Description Current stutiis Afon Clywedog (Dee) Problem caused by natural PWS sources to be abandoned and conditions, exacerbated by PWS licence revoked. abstraction. Garrcn Brook (Wye) Problem may be due to spray No new summer abstraction licences irrigation abstraction. will be granted. Further work required. River Gamber (Wye) Abstractions for spray irrigation No new nett summer abstraction may be having an impact. licences to be granted. Gauging station being recommissioned to monitor flows and obtain data for further investigation. Afon Llynfi (Ogmore) CMP identified low flow problem. Work planned to provide additional Abstractions for industrial use water to river when depicted. affects river flows. Afon Ritec (Tenby) CMP identified low flow problem. Observation boreholes installed to help monitor and identify scale and potential cause of problem. Located in licence-exempt area. Afon Porthllwyd (Conwy) CMP identified low flow problem Further work required to assess downstream of dam used for HEP. severity of problem. Alford Brook (Dee) CMP identified low flow problem. Investigation heing undertaken. Base flows may be reduced by long Enhanced monitoring established to tenn drop in groundwater levels. assess rate of reduction of baseflows. Worthcnhury Brook CMP identified low flow problem Investigation being undertaken. (Dee) (linked to above site). Dolfechlas Brook (Dee) CMP identified low flow problem. Further work required to assess severity of problem. An alleviation plan has recently been formulated by the NRA and WEWDC, under which WEWBC will abandon the Minera sources and NRA will revoke the licence. The loss of supply will be made good through additional abstraction from the Company’s existing intake on the River Dee. The Company’s total yield will remain unchanged, but the total licensed quantity will reduce by 3.6 Ml/d, the difference between the Minera sources current yield of 2.5 Ml/d and the 6.1 Ml/d licence entitlement. WEWDC will gain a more reliable source with better quality water, but with higher operating costs and some initial capital expenditure. The Afon Clywedog will benefit from increased flows. The Clywedog Valley downstream of Minera contains a number of sites of local and national archaeological importance, and is the setting for a 12km Heritage Trail created by Clwyd County Council. Additional water will benefit not only this important amenity use. but also Water quality and fisheries. 4.6.1.2 Aldford Brook/Worthenbury Brook These sites are of major concern from a resources viewpoint as. on top of local environmental impact, these streams are small but important contributors to the baseflow of the lower Dee and therefore the low flow problem impacts on the yield of the Dee. The Page 60 WRWRS.REP/75F/27 Jane 1994 cause of the problem has yet to be identified. However, STWP abstractions at Overton Scar, Tower Wood, and one other location across the border are thought to be mining water. The NRA is currently undertaking an investigation to identify the cause of the problem and assess amelioration options. If the STWP abstractions are found to be the cause of the problem then it may be possible to augment the abstractions with water from Vyrnwy aqueduct during summer months in order to rest the aquifer. 4.6.1.3 Afon Alyn In the case of the Afon Alyn, investigation has shown that natural limestone river bed drainage, exacerbated by mining, rather than as a result of abstraction. Subsequently the river is dry every year over a large stretch. The water drains to the Bagillt tunnel on the Dee estuary where Dwr Cymru have an abstraction for non-potable supplies. Studies (Ref 21) to alleviate the low flow identified that a pipeline or channel to bypass the affected river stretch could maintain baseflows during the summer period, equating to approximately a 10 Ml/d increase in the yield of the Dee. However, this could lead to derogation of the licence at Bagillt. The preferred solution identified has not been implemented due to high cost with limited benefit. As a result the NRA will only continue to evaluate local remedial measures specific to the lower Alyn. 4.7 NATIONAL WATER RESOURCES DEMANDS The Welsh Region is already a major net exporter of resources to other Regions. The NRA is currently looking at future water resources at a national level as well as a regional level. At this strategic level, the South and South Hast of England are of particular concern because they: * have the highest anticipated increase in demand; * receive the lowest rainfall; * already have highly developed resources; * have the most low flow problems associated with overabstraction. A National Water Resources Strategy document was published by the NRA for discussion in 1992 (Ref 8). The preferred NRA strategy for future development of water resources to meet the needs of PWS, industry and agriculture was published recently for consultation (Ref 22). The preferred NRA strategy identifies a number of preferred options to meet marginal demands arising under a range of demand forecasts. The Welsh Region, with its relatively abundant water resources and small increase in demand (under low and medium growth scenarios), does not have a need for new strategic supplies. However, it may have an important role to play - as a potential provider of water for transfer to other Regions in the South and South East of England. Table 4.12 lists the eight options that have been identified and appraised in the National Strategy. Only Option 2 has implications for the Welsh Region. This is considered below. Further, detailed studies would he required before any new inter-basin transfer was approved, including environmental appraisals. Water resources developments will only be required under medium and high demand growth scenarios, with the marginal demand focused on the Thames Region. WRWRS.REP/75F/27 June 1994 Page 61 4.7.1 Enlargment of Craig Goch Reservoir There is considerable scope to enlarge Craig Goch Reservoir (one of the Elan Valley reservoirs). The scheme was extensively investigated in the 1970s, when a number of sub options of varying complexity were identified. An enlarged Craig Goch, with a top water level 49m higher than present and storage of 190,000 Ml, could be used to provide increased regulation of either the River Wye or, via catchment transfer arrangements, the River Severn. This in turn could support transfers to the River Trent or Thames catchments. Table 4.12 Preferred options in the National Water Resources Strategy O ption Scheme Additional potential yield ref. (Ml/d) 1 Severn-Thames transfer 57 -9 2 2 Enlarged Craig Goch Reservoir Up to 775 3 Partial redeployment of Vyrnwy Up to 337 Reservoir 4 S.W.Oxfordshire Reservoir 350 5 Severn-Trent transfer Capacity 100 6 East Anglian reservoir Capacity 174 7 Trent-Anglian transfer Capacity 200 8 Canal transfer to Thames Capacity 100 The enlargement of Craig Goch can be achieved by construction of a comparatively small new dam at the downstream narrow neck of a long, wide valley. The development would not have any significant community impact due to its remoteness, hut it would result in the inundation of part of the Elenydd SSSI and some other sites of nature conservation. Any proposals affecting these habitats would need to be carefully assessed and would meet with strong objections from the Countryside Council of Wales due to their national importance. Regulation releases to the River Wye would be made via a tunnel above Rhayader. An abstraction for transfer to the River Thames would be made at an intake in the vicinity of Ross-on-Wye. Further regulation of the Wye raises a number of concerns since the whole river, including riparian habitats, has been classified as a SSSI and as such is of national importance. The Wye is also an important salmon river. Although river flows are already affected by impoundments in the headwaters and periodic regulation releases, there is concern that the salmonid spawning reaches of the Upper Wye may be affected by an altered flow regime. However, moderation of extreme low flows may provide some benefit in terms of reduced environmental risk and improved habitat stability. An enlarged Craig Goch offers the potential to transfer water to the River Severn to support downstream demands including the possible transfers to the Trent and Thames basins. This would require a tunnel discharging at Llanidloes. Regulation of the River Severn with water from the enlarged reservoir would be in addition to that currently made from Clywedog and to a lesser extent Vyrnwy Reservoir. The effects of additional regulation would need to be evaluated and the loss of water from the Wye catchment would also need careful scrutiny. Page 62 WR WRS. REP/75F/27 June 1994 4.7.2 Other options Three other major resource options have been investigated as part of the National Strategy: two new reservoirs - one in Oxfordshire (Thames Water Services has proposed a 150,000 MI storage reservoir near Abingdon) and one in Anglian Region (two possible sites for a pumped storage reservoir, at Great Bradley or Shrubhill, in Norfolk), and redeployment of Vyrnwy Reservoir for regulation of the River Severn. The three transfer schemes (Severn to Trent, Severn to Thames, Trent to East Anglia) all involve transfers of large quantities of water between major basins. These proposals have major environmental implications which are being examined. 4.8 AFFORESTATION Afforestation raises important issues for water resources. The preparation, planning and final development of forests, and management practices associated with forests can have major impacts on both catchment response to rainfall and the quality of runoff. The major thrust of afforestation began in the early 20th century, when forests were encouraged around reservoirs and in the water-gathering grounds to reduce the effects of bacteria from sheep waste and to prevent soil erosion. The Forestry Commission’s planting of timber following the Second World War was designed to reduce the country’s reliance on imported timber. In the 1990s, following acceleration in forestry in the 1970s and 1980s, environmental concern and tax law reform have led to a hiatus in the afforestation programme. Studies (Refs 23,24,25) have found that afforestation can result in reduced yields of water sources. The principal mechanisms for this reduction are increased transpiration and evaporation from the wetted tree canopy compared with open moorland. In general terms impact depends upon the type of trees being planted and the vegetation being replaced. Broadleaf planting tends to be preferable to coniferous as they should have less impact on water quality and quantity. Hydrological changes may also alter erosion and deposition patterns along a river, and lead to increased river maintenance costs. Furthermore sedimentation from increased erosion may directly affect storage reservoirs by reducing their capacity. Afforestation may also cause changes in flood response of streams, particularly in ploughed and drained catchments. Upland storage reservoirs are important in the Welsh Region for provision of drinking water of high quality and for river regulation purposes. Forestry development within the catchments of such sources may have significant implications for the costs of supplying water, particularly if losses of yield necessitate provision of additional resources. Afforestation, in the particular case of HEP generation, causes direct loss of generation by reduction in the amount of water which is available to run the turbines. The Powergen scheme at Rheidol and the Nuclear Electric scheme at Trawsfynydd/Maentwrog are thought to he the only HEP schemes affected by afforestation. In normal operation, the Welsh HEP schemes are used for. "peak lopping", generating at times of daily peak demand on the National Grid. If HEP generation is not available because of water loss, it has to be replaced, and at peak times such replacement will be from one of the less efficient coal, oil, or nuclear thermal power stations. Additionally, because of their fast response, HEP schemes can be used to respond to short-term demand fluctuations, and if they are not available this function can only be performed by gas turbines, which are extremely expensive to run. WRWRS.REP/75F/27 June 1994 Page 63 The Forestry Enterprise (FE) and the Forest Authority (FA) act as the Commission’s executive wings. The FE is responsible tor public sector forestry management and development, currently managing about 135,000 hectares of forestry in the Welsh Region. The FA administers private sector development under the Woodland Grant Scheme (WGS), with about 120,000 hectares of forestry in the Welsh Region under FA administration. Discussions with both organisations (see Appendix I) indicate that there have not been any new major forestry development in the last few years, and the only planned development amounts to 450 hectares (under the WGS). Afforestation is therefore not deemed to present a problem for the future water resources of the Region. Page 64 WRWRS.REP/75F/27 June 1994 5 OPTIONS FOR A STRATEGY FOR WATER RESOURCES 5.1 INTRODUCTION As explained in Section 1 the NRA has a statutory duty to conserve, redistribute or otherwise augment water resources and secure the proper use of those resources. To meet this important obligation a strategy is required to meet the future water requirements of the Region, optimising those resources in a sustainable manner, and ensuring, that water demands are met in an environmentally acceptable manner. The NRA’s principal aim is to achieve a balance between the needs of abstractors and the those of the environment. The NRA is specifically responsible for licensing abstractions made from water held in natural underground storage and from ail surface waters above the tidal low water mark (excluding certain licence-exempt areas). This is one of the key water resources activities and is fundamental in shaping how water resources are used and how the water environment is managed. The NRA applies the precautionary principle where the impact of abstraction is uncertain. The NRA also has general environmental duties, in relation to all its functions including the need to further conservation. The Authority also has duties to promote the use of inland and coastal waters for recreational purposes. In Section 4 forecasts of future PWS demands were made under a range of scenarios. Table 5.1 summarises the marginal demands. Section 4 also identified increases in private demands for spray irrigation and HEP and highlighted some issues associated with non consumptive uses. Table 5.1 Summary o f PWS marginal demands in 2021 Water company Marginal demand (Ml/d) Low growth Medium growth High growth CWC 7.4 (2001) 9.7 (2006) 13.0 (2001) WEDWC - 3.5 (2011) 8.4 (2006) Dwr Cymru SE area 0.2 (2016) 0.8 (1996) 39.0 (1996) SW area 9.1 (1996) 14.1 (1996) 26.9 (1996) NE area 0.1 (2021) NW area 0.1 (2016) 0.2 (1996) 11.8 (1996) REGION TOTAL 16.8 28.3 99.1 Note - Figures in brackets are start date for deficit. In this Section options available for meeting these demands are explored. These comprise encouraging efficient use of water and adoption of water saving methods, re-allocation of water and making more water available. The marginal demands arising in the Region are relatively small. WRWRS. REP/75F/27 June 1994 Page 65 The NRA has issued the following national policy statement: "Before any new sources are developed, it is essential that water companies make sure they are doing all they can to reduce leakage and carry out effective demand management. The NRA supports the use of selective domestic metering, with an appropriate tariff, in areas where water resources are stressed.” As the high growth scenario assumes no improvements in leakage levels or metering, which is contrary to NRA policy, options to meet the high growth scenario are only outlined, with the focus on options to meet the low and medium growth scenario forecasts. Groundwater development, effluent re-use and other esoteric options are discussed, but these options are not investigated in detail as they are not appropriate at this time given the scale of the forecast marginal demand in the Region. 5.2 THE OPTIONS FOR SAVING WATER - DEMAND MANAGEMENT The provision of all water resources involves a cost, both financial and environmental. As the population grows so does the demand for water. It is therefore important that these demands are managed to keep them as low as reasonably practicable. Management initiatives include leakage control and metering. The NRA already advocates demand management by all water users to the extent that it is economically justified. The principles of demand management are being increasingly recognised, and fostered for example in the Government’s discussion paper "Using Water Wisely" (Ref 26). Options for saving water are discussed in the following Sections. 5.2.1 Leakage reduction Existing and future demands can be reduced by minimising leakage. This can play an important role in reducing the need for development of new water resources. Additionally, leakage is costly in supply terms since the costs incurred in treating and supplying water are wasted. However, it should be borne in mind that leakage reduction is subject to the law of diminishing returns, and realistic targets for leakage reduction need to be set. Economic levels of leakage vary from company to company, depending upon the cost of leakage and of leakage control activities, as well as the underlying level of leakage due to the physical nature of the supply system. Total leakage consists of distribution losses (company leakage) and supply pipe leakage. There is some debate on how to assess leakage with differences in approach between water companies. Table 5.2 shows leakage data for the water companies in the Region to illustrate the variation in distribution losses (Ref 17). It is hoped that better information will become available from the National Leakage Initiative - a project set up by the Water Services Association and the Water Companies Association. CWC and WEDWC have actively practised leakage control for a number of years and have total leakage levels below the national average. Additionally, their leakage levels are below the target levels set for PWS in the National Water Resources Strategy demand forecast scenarios, upon which the methodology used in this report has been based. However, a level of diminishing return has been reached and further significant reductions are only likely following major capital investment on water supply systems, in particular the replacement of ageing water mains. CWC’s and WEDWC’s marginal demands - 9.7 Ml/d and 3.5 Ml/d respectively under the medium growth scenario - will therefore have to be met by other means. Page 66 WRWRS.REP/75F/27 June 1994 Table 5.2 Leakage levels in the Region in 1992 Water Company Distn. losses Total leakage Supply pipe /Distn. input (1/prop/hr) leakage/Total (as a %) leakage (as a %) Dwr Cymru 28 15.6 21.6 CWC 14 7.0 29.9 WEDWC 12 6.0 27.3 National average 17 8.5 28.5 Dwr Cymru have a higher level of leakage than the two smaller companies, with distribution losses substantially above the national average at 28% of distribution input, reflecting the poor state of Dwr Cymru’s supply system. The Company is undertaking a programme of leakage reduction, especially in the South East Division. However, it should be noted that this apparently high figure may be due to the way in which the Company has assessed leakage as D&r Cymru’s figure for supply pipe leakage is significantly lower than those for CWC and WEDWC and the national average. At 15.6 1/prop/hr Dwr Cymru’s level of leakage is significantly greater than the target levels used in the national strategy demand forecasts (Medium forecast - 11 1/prop/hr; High forecast -14.5 1/prop/hr). Clearly, if Dwr Cymru reduce their levels of leakage in line with the medium growth forecast the need for new resource development over the planning period will be minimal. 5.2.2 Metering of domestic water use Metering of domestic use, with appropriate tariffs, is probably the most effective way of reducing water use. Current national metering trials have been running for three to four years. Preliminary results indicate that average domestic consumption can be reduced by 11%, and peak demands by as much as 30%. There is uncertainty as to whether in the longer term such significant reductions in demands can be maintained without invoking special tariffs, but in some other countries metering plays an important role in demand management as evidenced by the growth in water-saving appliances. Additionally, as with leakage reduction there is a law of diminishing returns with metering, as well as practical, economic and social factors which influence the rate and extent to which meters are introduced. CWC and WEDWC both have a policy of metering all new properties. Dwr Cymru have stated their intention not to move towards universal metering, because they consider that up to 90% of the cost of supplying domestic properties is independent of the volume of water taken. The Company’s current policy is to only install a meter upon request from the customer. Dwr Cymru believe that in many parts of their area the cost of installing, maintaining, reading and billing meters would be several times greater than the value of the small percentage of delivered water which would be saved. However, recent advances in meter reading technology mean that the cost of reading can be reduced substantially. In light of this the NRA may expect Dwr Cymru to amend its policy. WRWRS.REP/75F/27 June 1994 Page 67 5.2.3 Consumer education Consumers can play their part in reducing demand by reducing their own use of water. The NRA has taken a lead in this direction ever since its formation, and it is recommended that the NRA continues to endorse moves to educate the public to use water wisely. However, most savings are more related to saving peak distribution costs than water resources. 5.2.4 Better design of water appliances Water can be saved by improved design of washing machines, dishwashers, and other appliances, and by reducing the flush-volumes of wc’s. It may require price incentives to achieve a real impact on appliance design, and there are social and public health limitations to be considered. 5.2.5 Industry There may be scope for industry to save water by more efficient processes and/or by re cycling water within the factory. The Centre for Exploitation of Science and Technology (CEST) is currently undertaking a project in conjunction with industry to demonstrate the benefits of waste minimisation and cleaner technology (Ref 27). In the first 18 months of the project the eleven participating companies made savings of over £2M a year. Reductions in the use of inputs such as water, energy and raw materials exceeded savings in effluent production by a significant margin thereby confirming that companies can profit from cleaner production through improved process efficiency. The NRA should continue to encourage industry to practice good water husbandry. 5.2.6 The National Abstraction Charging Scheme The national scheme of abstraction charges was introduced on 1st April 1993. It provides a consistent basis for charges throughout England and Wales. The scheme incorporates a limited range of incentives to aid in the proper management of resources: * charges are set to encourage abstractors to use water efficiently and keep their licensed volumes to a minimum. The NRA also audits applications to ensure that applicants do not apply for more water than they reasonably require; * charges reflect the higher cost to the environment of summer abstractions; * charges are lower for less consumptive uses of water. The application of incentive charging as an economic instrument to control the environmental impact of abstraction may be developed further. Incentive charging would however require a change to the legislation if the NRA needed to recover more by way of charges than its year on year expenditure, in order to provide a real incentive to change attitudes and behaviour. Page 68 WRWRS. REP/75F/27 June 1994 5.3 THE OPTIONS FOR RE-ALLOCATING WATER The system of licences introduced by the Water Resources Act 1963 allocates water to the first person or organisation to show a reasonable need for it. The system is a rigid one of first come first served, and once issued a licence confers a valuable right on the holder. Recently it has become more common for licences to be time limited, but generally only for reasons of uncertainty over water availability, and most licences are valid until revoked. The only way to re-allocate water is for the NRA to revoke an existing user’s licence, then reissue it to a new user. This makes sense if the value of water to the new user is greater than the value to the old user. However, the NRA has to pay full compensation to the old user, and may gain no increase in licence income. Many of the licences in the Region are approaching 30 years old, may not have been efficiently issued and may now be inappropriate. The decline in abstraction evidenced by returns from industrial users would serve to indicate under-utilisation of licences and may not reflect current best use of water. 5.3.1 Under-used licences and 'inefficiently* used licences The term ‘inefficient’ is used in its economic sense, meaning water allocated by licence to a relatively low-value use when there is an alternative high-value use needing water. Research into the economics of water resources management (Ref 10) concluded that the most appropriate way to deal with this situation, bearing in mind the incentive on licence- holders not to give up their rights and the penalties on the NRA of revocation, would be a system of tradeable permits. This would allow a free market in licensed abstraction rights (with a regulatory role by NRA). In theory in the long term this could lead to the allocation of water to the highest value users. 5.3.2 Incentive charging The charges for water abstraction must, by law, be set to balance the costs of managing water resources. They are therefore relatively low, and are in no way related to the value-in- use of water, nor the cost of making ‘new’ water available. The NRA is therefore looking into whether economic principles, particularly incentive charges, could be used to improve management and allocation of water resources. However, it is too soon to build any assumptions ahout this into this strategy. 5.4 OPTIONS FOR MAKING MORE WATER AVAILABLE There are various ways in which more water can be made reliably available. Howe' er, most of them involve significant cost and/or environmental impact. It should be remembered that responsibility for identifying need and making proposals for new resource schemes to meet PWS demand lies with the water companies. The NRA is in regular dialogue with each of the companies in the Region. Options to meet the forecast marginal demands are discussed below and detailed in Tables 5.2-5.15 at the end of this Section. The Tables include an outline assessment of potential environmental impacts, and costs which are given at fourth quarter. 1993, prices. WRWRS.REP/75F/27 June 1994 Page 69 5.4.1 Local source developments and extensions W inter water is relatively plentiful and can be stored for summer use. The low winter abstraction charges act as an incentive to farmers to use storage reservoirs to meet irrigation demands. The minor aquifers and some of the rivers of the Region provide storage that can be utilised to sustain small local supplies. It is arbitrarily assumed that local sources can meet all the forecast deficits for agriculture. Dwr Cymru have identified local source developments in parts of north Dyfed, Meirionnydd and Hereford & Radnor (Options 1 - 3). These developments comprise a mixture of small groundwater and surface water schemes amounting to about 50 Ml/d. The more urgent needs are in the north Dyfed and Meirionnydd areas, where the large distances between centres with very small populations make sub-regional schemes an uneconomic option. In addition to the above new source developments, a small increase in the use of Cowlyd Reservoir for PWS could be implemented to meet the deficit arising in the Cowlyd supply zone (Option 4). 5.4.2 Regulated rivers - use of spare unlicensed yield Of the six regulation schemes in the Region only one, the Tywi scheme,is believed to have significant spare unlicensed yield at present. There is thought to be an unlicensed yield of 10 Ml/d which could be utilised to meet marginal demands in Dwr Cymru’s supply area. STWP are believed to have an interest in increasing their licensed abstraction of 45 Ml/d from the Wye at Lydbrook. If this is the case, there is a potential problem with any future applications for abstractions from the Wye and its tributaries tor spray irrigation. The river regulating capabilities of the Elan Valley reservoirs appear to be fully exploited under the present Operating Agreement. It is unlikely that the yield of the River Wye for regulated abstractions can be increased, unless STWP are prepared to reduce their direct supply from the Elan Valley reservoirs in dry years in order to make a little more water available for abstraction at Lydbrook. Until recently it was thought that there was a spare unlicensed yield of about 40 Ml/d in the river Dee. However, preliminary results from an ongoing project - commissioned by the NRA - which is undertaking a periodic reassessment of the yield of the major regulated rivers indicate that there is probably no spare yield in the River Dee system as presently regulated using the available storage in Llyn Celyn, Llyn Brenig and Llyn Tegid (Refs 28.29). However, about 100 Ml/d of NWWL’s combined licence of 686 Ml/d from the river at Chester is known to he surplus to both their current requirements and the combined treatment works capacity. It may be possible to negotiate with NWWL either to relinquish part of this licence or to agree that it shall be used for an inter-basin transfer to their Oswestry treatment works so as to make part of the yield of Vyrnwy Reservoir available for regulation of the River Severn. The latter consideration, however, is outside the scope of this report. There may he very limited scope for licensing further abstractions from the regulated Rivers Usk and Eastern Cleddau, for which Section 20 Agreements were originally proposed but not implemented. Page 70 WRWRS.REP/75F/27 June 1994 5.4.3 Regulated rivers - increases in yield Two modest schemes to increase the regulated yields of the rivers Dee and Tywi are described below. Schemes to provide large increases in the yield of some the regulated rivers, involving major raising of the dams at Llyn Brenig, Llyn Brianne and Llys-y-fran are not detailed as they are not appropriate given the scale of forecast marginal demands. 5.4.3.1 Augmentation of the River Dee When the Brenig scheme was promoted in the early 1970s it was intended that the reservoir as originally constructed should be substantially enlarged at a later date in order to increase the regulated yield of the River Dee by some 270 Ml/d by providing multi-season pumped storage for surplus water from the upper Dee and some of its tributaries. However, as explained above, it is now thought that the long term average run-off in the Upper Dee catchment is not sufficient for there to be value in raising the dam substantially and constructing the three intended river intakes and pipelines to the reservoir. It should be noted that the necessary three abstraction licences for the transfer of water to the reservoir were issued in 1972, but that these authorise the abstractions only when there is surplus water in the Dee and its tributaries. These three licences allowed for pumping up to 84,000 Ml/a at rates of up to 400 Ml/d, which would have required the construction of three large capacity pumping stations and delivery through three large diameter trunk mains. It is unlikely that the construction of a scaled down version of these works to transfer much smaller daily quantities of water from the River Alwen and the River Dee into Llyn Brenig in its present "Stage 1" form would prove economic as it would to be very costly in relation to the marginal increase in the yield of the reservoir which would be achieved. In other words the three licences are of no value to the Dee regulation scheme if Stage II of Llyn Brenig is not constructed. It appears that there is not sufficient water in the Dee and its tributaries to make Stage II a viable proposition. Dwr Cymru have recently abandoned the use of Llyn Bran (a small impounding reservoir at the head of the Brenig catchment) for direct supply purposes. This results in an increase of about 1.2 Ml/d in the average run-off into Llyn Brenig. D&r Cymru propose to construct a gravity pipeline from Llyn Brenig to the new Alwen treatment works which will increase the output of these works by allowing Alwen Reservoir to be overdrawn in dry years. The Company could enhance the long term yield of Llyn Brenig by constructing a low lift pumping station to transfer surplus water in wet years from Alwen Reservoir, using their proposed pipeline in the reverse direction. It is believed that these measures would increase the regulated yield of the Dee by 15 to 20 Ml/d (Option 5). The value of Llyn Celyn as a means of regulating the River Dee is restricted by draw down rules which are necessary to ensure that a probable maximum flood (PMF) would not cause overtopping of the crest of the dam. A modest raising of the dam crest, with no increase in top water level, would increase the regulated yield of the River Dee by some 20 to 25 Ml/d (Option 6). In summary, there may be scope for augmenting the regulating yield of the River Dee by 35 to 45 Ml/d by implementing the modest schemes outlined above. WRWRS.REP/75F/27 June 1994 Page 71 5.4.3.2 Augmentation of the River Tywi The use of Llyn-y-fan Fach impounding reservoir for direct supply purposes has recently been abandoned. Its capacity is equivalent to a raising of Llyn Brianne by 0.4 m and it could therefore augment the regulated River Tywi by 5 Ml/d in dry years (Option 7). Schemes were recently prepared to increase the top water level of Llyn Brianne by 1 and 2 metres (Option 8) with corresponding increases of Vh% and 7% in the capacity (Ref 30). The present reassessment of the regulated yield of the existing reservoir will no doubt produce figures for the marginal increases in yield which would be provided by a 1m or 2m increase in top water levels. The provision in the original design for an increase of up to 15m assumed that a tunnel would need to be constructed to the headwaters of the River Irfon, a tributary of the River Wye, which would have necessitated a partial drawdown of the reservoir that would be difficult to achieve after the yield of the reservoir as constructed has been substantially taken up. 5.4.4 Inter-basin transfers Several inter-basin transfer schemes could be implemented to augment the yield of the regulated River Usk and to deliver water to supply zones remote from resources. A proportion of the uncommitted yield of the regulated River Tywi, after a 2m raising of Llyn Brianne, could be utilised to augment flows in the River Usk in either one of two ways:- (i) Water abstracted from the River Tywi near Llandovery and pumped via a new pipeline to the head of a tributary of the River Usk near to the Halfway public house when regulation is taking place (Option 9); or (ii) Water abstracted from Llyn Brianne delivered by gravity pipeline to the same discharge point at the headwaters of the River Usk (Option 10). Option 9 would prove more economic for the transfer of smaller quantites of water on a seasonal basis. Option 10 would be justifed for the transfer of larger quantites of water on a regular basis. Before detailed hydrological and engineering assessments are undertaken it would be necessary to make an appraisal of the scheme’s implications for fisheries arising from the introduction of water from the Tywi into the Usk. Inter-basin transfers can give rise to significant environmental implications as a consequence of introducing water from one catchment into a major watercourse in another catchment. If this scheme were to be adopted a detailed environmental appraisal would he required before it could proceed. In order to meet marginal demands in Dwr Cymru’s South West Division an inter-basin transfer could be implemented from the Tywi to Pembrokeshire, via a new trunk main from the existing pumping station at Nantgaredig (Option 11). This would utilise some of the unlicensed yield of the River Tywi to meet demands the eastern part of the Pembrokeshire supply zone, as an alternative to increasing the regulated yield of the Eastern Cleddau by increasing the top water level of Llys-y-fran Reservoir by 1.7 metres. Dwr Cymru is believed to be seeking an increase in its abstraction licence at Nantgaredig. In 1992 the Company deferred the need for such a main by raising the top water level by 1.7m for a very modest expenditure. Page 72 WRWRS.REP/75F/27 June 1994 If and when the forecast demand of this supply zone approaches the yield of the various sources supplying it, including the extra 7 Ml/d now available from the Eastern Cleddau, the transfer of water from the River Tywi will again become a serious option. In order to justify the cost of constructing a trunk main some 25km in length, the size of the transfer would have to be of the order of 20 Ml/d. By reallocation of demands between the existing treatment works at Capel Dewi (near Carmarthen) and Felindre (north of Swansea) Dwr Cymru may be able to deliver treated water through the proposed transfer main. The scheme would, like the Nantgaredig-Felindre, Usk-Llandegfedd and Wye-Court Farm schemes, abstract water from one catchment and deliver it via trunk mains and treatment works to distribution systems in other catchments. The yield of the River Dee could be increased by a transfer scheme to divert water from the upper end of the Conwy catchment into Llyn Celyn. However, this scheme would provide only a small increase in the yield (Option 12). ♦ 5.4.5 Conjunctive use schemes The three water companies have already developed conjunctive use schemes to a very considerable extent. Also, NWWL’s single abstraction licence for their three abstraction points on the Dee upstream of the tidal limit at Chester weir enables them to use these three sources conjunctively. Dwr Cymru’s southern conjunctive use area accounted for 46% of the company’s total potable water demand in 1992-93. At present 4% of the demand in this supply area is supplied by a transfer main from the adjacent Felindre conjunctive use zone which itself accounted for a further 20% of the total demand. Works are currently in progress to enable some of the forecast increase in demand in the Southern CUA to be met by increasing this transfer so as to take up some of the presently unused treatment capacity at Felindre. In a sense the two areas therefore use the same group of sources conjunctively. If the TvwUUsk transfer scheme proved to be a viable option, this would ensure that the regulated output of Llyn Brianne, possibly enhanced by raising the dam 2m, became available to meet future demand increases across south Wales from Pembrokeshire to Gwent, conjunctively with the other existing sources in this large area. 5.4.6 Recupimissioning of Schwyll source The Schywll source is located near Bridgend in South Wales. It draws water from major fissure systems in the Carboniferous Limestone. Water enters the fissure systems from surface water flows via ‘sink holes’ in river beds. Dwr Cymru plan to "moth-ball" the Schwyll source in 1994/95 because of the high cost of improving the treatment plant to meet European Union standards compared to the cost of using presently surplus water from Felindre in the South West Division. This source has been excluded from the reliable yield for the South East Division. By 2016 when the resources of the South East CUA may be fully utilised it may economic to recommission Schwyll pumping station and treatment works to provide an additional resource for this CUA (Option 13). WRWRS. REP/75F/27 June 1994 Page 73 Table 5.3 Option 1 - Local supplies in Hereford and Radnor area Physical Small groundwater and surface water schemes. description and feasibility P otential Local PWS in Dwr Cymru S.E. supply area. beneficiaries Yield 5 to 20 Ml/d Construction £0.1-0.5M per Ml/d costs (Q4 1993) Operating costs £10-20K per Ml/d (Q4 1993) Environmental Hydrology No significant adverse impacts envisaged. Risk of im pact derogation to downstream abstractors. Hydrogeology Risk of impact on private boreholes and wetlands. Water quality Surface waters good quality. Risk of contamination to shallow aquifers. Appropriate licence conditions required. Flood defence None foreseen. Fisheries Impacts to be assessed at scheme promotion Recreation/Navigation None foreseen Social impact Minimal. P lanning Sites will be chosen which have least potential adverse planning implications implications. Other benefits These small schemes will only be promoted by Dvvr Cymru in & constraints situations where a forecast local yield deficiency cannot be more economically met by importing surplus water from an adjacent supply zone. Demand An appropriate level of demand management would be required m anagem ent prior to scheme development. Page 74 WRWRS.REP/75F/27 June 1994 Table 5.4 Option 2 - Local supplies in North Dyfed area Physical Small groundwater and surface water schemes in an area description and where such schemes are feasible. feasibility Potential Local PWS beneficiaries Yield 5 to 10 Ml/d Construction £ 0 .1-0.5M per Ml/d costs (Q4 1993) Operating costs £10-20K per Ml/d (Q4 1993) Environmental Hydrology No significant adverse impacts envisaged. Risk impact of derogation to downstream abstractors. Hydrogeology Risk of impact on private boreholes. Water quality Rivers of good quality except Afon Rheidol. Risk of contamination to shallow aquifers. Appropriate licence conditions required. Flood defence None foreseen. Fisheries Impacts to be assessed at scheme promotion. Recreation/Navigation None foreseen. Social impact Minimal. Planning Sites will he chosen which have least potential adverse implications planning implications. Other benefits These small schemes will only be promoted by Dwr Cymru in & constraints situations where either a forecast local yield deficiency cannot more economically be met by importing surplus water from an adjacent supply zone, or where no such surplus exists. Demand An appropriate level of demand management would be management required prior to scheme development. WRWRS. REP/75F/27 June 1994 Page 75 Table 5.5 Option 3 - Local supplies in Meirionnydd Physical Small groundwater schemes in an area where such schemes description and are feasible. feasibility Potential Local PWS beneficiaries Yield 5 to 20 Ml/d Construction £0.1-0.5M per Ml/d cost (Q4 1993) Operating costs £10-20K per Ml/d (Q4 1993) Environmental Hydrology No significant adverse impacts envisaged. im pact Hydrogeology Impact on private boreholes to be assessed. Water quality Appropriate licence conditions required. Flood defence None foreseen. Fisheries None foreseen. Recreation/Navigation None foreseen. Social impact Minimal. Planning Sites will be chosen which have least potential adverse implications planning implications. Other benefits These small schemes will be promoted by Dwr Cymru in & constraints situations where either a forecast local yield deficiency cannot be more economically met by importing surplus water from an adjacent supply zone, or where no such surplus exists. D em and An appropriate level of demand management would be m anagem ent required prior to scheme development. Page 76 WRWRS.REP/75F/27 June 1994 Table 5.6 Option 4 - Extension of Cowlyd Reservoir Physical Extension to treatment works and distribution system for description and increase in direct supply yield of reservoir. feasibility Potential PWS beneficiaries Yield 3 Ml/d Construction <£2M costs (Q4 1993) Operating costs £50K/a (Q4 1993) Environmental Hydrology None foreseen. impact Hydrogeology None foreseen. Water quality None foreseen. Flood defence None foreseen. Fisheries None foreseen. Recreation/Navigation None foreseen. Social impact None foreseen. Planning To be assessed at scheme promotion stage. implications Other benefits Cowlyd is the deepest lake in Wales, operated by Povvergcn & constraints for HEP. Dwr Cymru purchases water for PWS. No need to raise dam crest. Previous studies have identified available additional water for PWS. Demand An appropriate level of demand management would be management required prior to scheme development. WRWRS.REP/75F/27 June 1994 Page 77 Table 5.7 Option 5 - Pump surplus water from Uyn Alwen to Uyn Brenig Physical Construct pumping station to deliver surplus water from Llyn description and Alwen to Llyn Brenig. feasibility Potential PWS and other Dee users beneficiaries Yield 15 to 20 Ml/d Construction £0.9M costs (Q4 1993) Operating costs £137K/a (Q4 1993) Environmental Hydrology Significant impact on flow regime, especially im pact summer flows in Alwen and Dee. Hydrogeology None foreseen. Water quality Investigation needed into impact of transfer of poor quality water from Alwen to Brenig and Dee. Flood defence Impact/Potential of flood flow regulation to be checked. Fisheries Significant impacts of Dee regulation already recorded. Impacts of increased flows to be investigated. Recreation/Navigation None foreseen. Social impact None foreseen. Planning None foreseen. implications Other benefits Llyn Brenig was designed for raising by 21m but this is & constraints considered not to be a viable proposition. D em and An appropriate level of demand management would be required m anagem ent prior to scheme development. Page 78 WRWRS.REP/75F/27 June 1994 Table 5.8 Option 6 - Raise dam crest at Llyn Celyn by 1.5m Physical Raising the dam crest by 1.5m will enable the reservoir to description and pass a probable maximum flood with the present draw-down feasibility rules which restrict the yield. Potential PWS and other Dee users beneficiaries Yield 20 to 25 Ml/d Construction £0.70M costs (Q4 1993) Operating costs Nil (Q4 1993) Environmental Hydrology Change in flows within the range of flows in the impact Afon Tryweryn, although increase in low flows. Hydrogeology None foreseen. Water quality Celyn and Afon Tryweryn good quality water so no adverse impact envisaged. Flood defence Flood flow regulation to be assessed. Fisheries Significant impact on scouring in Tryweryn and further reduction in spawning grounds. Recreation/Navigation None foreseen. Social impact Nil. Planning Crest raising can be justified on reservoir safety grounds and implications TWL will be unchanged, therefore no planning problems foreseen. Other benefits Raising of the dam crest will not scar the downstream slope as & constraints the crest is wide enough to permit raising without downstream filling. No raising of the bell mouth overflow will be required. There will be a marginal increase in the HEP revenue as a consequence of the higher reservoir operating level. Demand An appropriate level of demand management would be management required prior to scheme development. WRWRS. REP/75F/27 June 1994 Page 79 Table 5.9 Option 7 - Uyn-y-fan Fach regulating reservoir Physical Existing impounding reservoir used tor direct supply may be description and used tor augmenting the regulated flow of the River Tywi. feasibility Potential PWS and other users in S.W/S.E Wales. beneficiaries Yield 5 Ml/d Construction Nil costs (Q4 1993) Operating costs £50K/a (Q4 1993) Environmental Hydrology Minor change in flows within the range of flows im pact in the Sawdde and Tywi, although slightly increased low flows. Hydrogeology None foreseen. Water quality Sawdde has good quality water therefore Tywi water may be improved. Flood defence Regulation of flood flows on Sawdde to be assessed. Fisheries Possible adverse impacts should be investigated. Recreation /Na vigat ion No adverse impact envisaged. Social impact None foreseen. Planning None foreseen. implications Other benefits The use of this reservoir for regulating the River Tywi could & constraints be incorporated in the existing Section 20 Operating Agreement between the NRA and Dwr Cymru. Demand An appropriate level of demand management would be ritanugement required prior to scheme development. Page 80 WRWRS.REP/75F/27 June 1994 Table 5.10 Option 8 - Raise top water level o f Uyn Brianne by 2m Physical Raise dam crest and top water level by 2m to increase the description and capacity and yield. feasibility Potential PWS in SW and SE Wales. beneficiaries Yield About 20 Ml/d Construction £0.65 M costs (Q4 1993) Operating costs Nil (Q4 1993) Environmental Hydrology Change in flows within the range of flows in the impact Upper Tywi. Increase in low flows. Hydrogeology None foreseen. Water quality Need to increase liming to balance acidity problem. Possible increase in adverse impact on water in Upper Tywi should be investigated. Flood defence Scope for flood alleviation in Tywi using additional capacity to be assessed. Fisheries Increased dry weather flows may have benefits for return of fish to upper reaches. Decrease in number of spills could reduce stimulus for fish movement. Impact of water temperature change on mixing to be assessed. Recreation/Navigation None foreseen. Social impact None foreseen. Planning Llyn Brianne was designed for raising by 12m which was implications acceptable in 1968. Therefore no planning problems are foreseen with the 2m raising. Other benefits Raising of the dam crest will not scar the downstream slope as & constraints the crest is wide enough to permit raising without downstream filling. Tree clearance was carried out to 3m above the original top water level. The Forestry Enterprise will lose access across the dam crest during raising. Demand An appropriate level of demand management would be management required prior to scheme development. WRWRS.REP/75F/27 June 1994 Page 81 Table 5.11 Option 9 - Tywi to Usk transfer I Physical Construct pumping station near to Llandovery to deliver water description and through a new trunk main to the head of an Usk tributary feasibility when regulation is taking place. Potential PWS and other Usk users. beneficiaries Yield 60 Ml/d Construction £9.6M costs (Q4 1993) Operating costs £240K/a (Q4 1993) Environmental Hydrology Significant change to Usk flow regime, with im pact increase in low flows. Hydrogeology None foreseen. Water quality Tywi and Usk good quality water, but transfer of water between catchments should be investigated. Flood defence Implications of intake and works in floodplain to be assessed. Fisheries Possible benefits to be gained from increased regulation if rate of release stable: Sea trout fishing important in Upper Tywi, but dependent on consistent flows with little variation in flow and level. Recreation/Navigation None foreseen. Social impact Disruption during construction. Planning To be assessed at scheme promotion stage. implications Other benefits The scheme would only operate intermittently as and when & constraints required to optimise conjunctive use of the Felindre and Southern conjunctive use areas. A detailed assessment of the various impacts would have to be investigated at scheme promotion stage. D em and An appropriate level of demand management would be m anagem ent required prior to scheme development. Page 82 WRWRS. REP/75F/27 June 1994 Table 5.12 Option 10 - Tywi to Usk transfer II Physical Construct gravity pipeline of 60MI/d capacity to deliver water description and from Llyn Brianne, via Llandovery, to the head of an Usk feasibility tributary. Potential PWS and other Usk users beneficiaries Yield 37 Ml/d Construction £19.8M costs (Q4 1993) Operating costs Nil (Q4 1993) Environmental Hydrology Significant change to Usk flow regime, with impact increase in low flows. Hydrogeology None foreseen. Water quality Tywi and Usk good quality water, but transfer of water between catchments should be investigated. Flood defence None foreseen. Fisheries Possible impact of reduced flows on the Upper Tywi. Recreation/Navigation None foreseen. Social impact Disruption during construction. Planning To be assessed at scheme promotion stage. implications Other benefits Possible adverse effect on potential HEP income from Llyn & constraints Brianne. A detailed assessment of the various impacts would have to be investigated at scheme promotion stage. Demand An appropriate level of demand management would be management required prior to scheme development. WRWRS.REP/75F/27 June 1994 Page 83 Table 5.13 Option 11 - Tywi to Pembrokeshire transfer Physical Construct pumping station at existing Capel Dewi treatment description and works to deliver water through a new trunk main to feasibility E.Pembrokeshire. Potential PWS between Carmarthen and Haverfordwest. beneficiaries Yield 20 Ml/d Construction £8.0M costs (Q4 1993) Operating costs £140K/a (Q4 1993) Environmental Hydrology None foreseen. im pact Hydrogeology None foreseen. Water quality Increased abstraction at Capel Dewi would require support of residual flow by increased regulation to prevent adverse impact on water quality in estuary. Flood defence None foreseen. Fisheries None foreseen. Tywi water would enter supply system directly. Recreation/Navigation None foreseen. Social impact Disruption during construction. Planning None foreseen. implications Other benefits This is likely to be more economic than a major raising of & constraints Llys-y-fran dam. D em and An appropriate level of demand management would be m anagem ent required prior to scheme development. Page 84 WRWRS. REP/75F/27 June 1994 Table 5.14 Option 12- Transfer Upper Conwy to Uyn Celyn Physical A low weir on the Afon Serw, a tributary of the Conwy, to description and divert the baseflow, via a 2km long catchwater of pipeline feasibility aqueduct, into the Afon Celyn. Potential PWS and other River Dee users beneficiaries Yield Small Construction <£0.5M costs (Q4 1993) Operating costs Nil (Q4 1993) Environmental Hydrology Minimal changes in flows in the Afon Conwy and impact Afon Tryweryn. Hydrogeology None foreseen. Water quality Celyn and Conwy good quality water so no adverse impact envisaged. Flood defence None foreseen. Fisheries Small impact on scouring in Tryweryn and further reduction in spawning grounds. Recreation/Navigation None foreseen. Social impact Nil. Planning None foreseen. implications Other benefits Dwr Cymru do not consider the scheme worth investigation at & constraints this stage. Impacts on the Dee system would have to be investigated in detail at scheme promotion stage. Demand An appropriate level of demand management would be management required prior to scheme development. WRWRS.REP/75F/27 June 1994 Page 85 Table 5.15 Option 13 - Recommission Schwyll source Physical The original pumping station and treatment plant are being description and decommissioned in 1994/95. New plant could be installed to feasibility improve water treatment at a relatively high cost. Potential PWS in South Wales area beneficiaries Yield 22 Ml/d Construction Unknown - likely to be relatively high (dependent upon costs (Q4 1993) required treatment standards at the time) Operating costs Unknown - likely to be relatively high (Q4 1993) Environmental Hydrology No impacts envisaged im pact Hydrogeology No adverse impacts foreseen Water quality Water treatment required to bring water up to quality standards for potable supply. Flood defence None foreseen. Fisheries None foreseen. Recreation /Na vi gat ion None foreseen. Social impact None foreseen. P lanning None foreseen. implications Other benefits Satisfactory treatment will be difficult to achieve and & constraints expensive. D em and An appropriate level of demand management would be required m anagem ent prior to scheme development. Page 86 WRWRS.REP/75F/27 June 1994 5.5 DEVELOPMENT OF GROUNDWATER RESOURCES Historically, the Welsh Region has always been perceived to have relatively abundant water resources, of which groundwater was considered to be an insignificant element. This led to a large part of the Region’s groundwater resources becoming licence-exempt (see Section 2.4.1). Today, most of the Region’s aquifers are acknowledged as being of only minor significance at a national level but are considered to be important in a regional context (Ref 4). The size of the resource is currently unknown, primarily as a result of historic preconceptions. The Welsh Water Authority (Ref 31) carried out a survey of the groundwater in its area as part of a Europe-wide project undertaken as part of the European Community’s Environmental Action Programme. This survey made an assessment of the gross groundwater resource based on aquifer outcrop areas and infiltration rates. The total gross resource was estimated as approximately 4000 Ml/d (averaged over 365 days). In the 15 years since this survey was carried out understanding of recharge mechanisms has improved and recent groundwater studies (Refs 32,33) have employed lower estimates of infiltration rates. Additionally, the inadequacy of aquifer storage to even out the year to year variations in recharge, means the effective resource can be substantially lower than the gross resource. In areas where the groundwater resources are better understood the reduction can be as great as 40% in the case of limestone aquifers (Ref 15). The effective groundwater resource for the Region is therefore likely to be of the order of 2500 Ml/d. This effective resource must support both human needs (abstractions) and environment needs (minimum river flows). Abstractions should not exceed the sustainable yield, that rate which can be sustained indefinitely without unacceptable reductions in groundwater level, discharge, or quality. It was explained in Section 3.7 that for the purposes of this strategy, in the absence of either defined minimum flow requirements or natural 95% flows, the reliable river allocation is conservatively estimated as 50% of the gross resource. This gives an estimated total resource available for abstraction of the order of 1250 Ml/d. Currently licensed abstraction from groundwater is about 300 Ml/d. It should be borne in mind that the exact size of abstractions from groundwater in the licence-exempt area is unknown and there are many small groundwater abstractions for domestic supplies. However, there is likely to he scope for some further development of groundwater. Some hydrogeological studies have been carried out to investigate the groundwater resources of some of the major groundwater units in the Region: * A study of the South Pembrokeshire Carboniferous Limestone aquifer (Ref 34) concluded that there were significant resources in both the shallow and deeper aquifer. Three potential development sites were identified with a combined resource estimated at 17 Ml/d. Dwr Cymru presently have abstractions at two of the three identified sites (Milton Springs and Pendine). * The South East Wales Groundwater Study (Ref 35) investigated the Carboniferous limestone aquifer outcropping around the edges of the South Wales coalfield. Insufficient data prevented an assessment of the reliable yield but resources were considered to be significant. * The Water Resources Board report on the Clwyd (Ref 36) concluded that the groundwater resource was about 21 Ml/d. Today, licensed abstraction amounts to about 20 Ml/d and the resource is considered to be exploited to its full potential. WRWRS.REP/75F/27 June 1994 Page 87 Groundwater in the Welsh Region is of good quality, with very few problems of elevated nitrate concentrations. Concentrations have been found to be rising in Gwent, Hereford and the Upper Wye, usually located on intensively farmed agricultural land. However, the demise of heavy industry in the Region and the presence of landfills on some of the major aquifers means water quality needs to be carefully monitored. The NRA is currently producing maps of groundwater vulnerability and source protection zones, which should be available in 1996. Dwr Cymru have a number of groundwater sources in the licence-exempt area of west Wales. The Company’s local source developments outlined above include groundwater schemes in Dyfed, Hereford & Radnor, and Meirionnydd, and there is not sufficient information available at this time to identify further specific options. The complexity of the Region’s hydrogeology and the lack of data hinder a regional appraisal, and, given the scale of the marginal demands arising over the planning horizon, only the limited local development of groundwater resources identified in Section 5.4.1. is required. 5.5.1 Use of minewaters as a resource Mining activities disturb the patterns of groundwater flow; groundwater discharges can be redirected by pumping or drainage adits, or simply by the interconnection between aquifers provided by the workings. Following the cessation of mining, groundwater levels recover. ‘Minewater’ breakouts occur as the water table reaches the surface. These minewaters represent a potential water resource in the Region, especially with the recent closure of three of the four remaining British Coal mines in Wales. Minewater discharges are generally characterised by a change in chemical quality (typically high iron concentration). In some cases these minewaters have a significant adverse effect upon the quality of river water and consequential detrimental effects on aquatic life. Discharges from both active and abandoned coal mines have caused pollution problems in the UK for many years. The NRA has recently undertaken studies to investigate the quality implications resulting from the recovery of groundwater levels to ‘natural’ equilibrium levels (Ref 37). The discharge of minewaters from working mines is controlled under current legislation through the consents issued by the NRA. Such consents will generally include conditions relating to the quality and quantity of the discharge. However, once mining ceases there is very limited control over any discharge because the overflow from mines which have been abandoned is exempt from control under current legislation. In a recent assessment of the use of minewaters as a resource (Ref 38) the NRA concluded that most potential sites were ruled out by constraints of quality and quantity, and the few remaining would only be suitable for non-potable supply on economic grounds. Such demands have not been identified. Treatment of minewater prior to discharge is feasible, but further work is required to assess the costs and benefits at individual sites. 5.6 USE OF EFFLUENT RETURNS The re-use of water can play an important role in optimising the use of limited resources. Whenever possible ‘used’ water should be returned to the river as close as possible to the source of abstraction. If quality can be maintained then this previously used water can be abstracted further downstream. Page 88 WRWRS. REP/75F/27 June 1994 About 30% of returning effluents (excluding discharges from coastal power stations) are discharged to inland waters and so are re-used, whether by abstractors downstream or as contributions to river baseflows. The remaining 70% or so are discharged to tidal estuaries or to the sea and are wholly lost to water resources. Clearly these effluents could be diverted and re-used. However, the direct re-use of effluent in the locality of its origin, though perhaps technically feasible with sophisticated treatment, may be undesirable on grounds of public perception. Furthermore, case studies have shown that the costs of piping effluent a long way up river, plus the additional treatment costs to the higher standard necessary, generally far outweigh the costs of other means of providing water resources. Given the scale of the forecast marginal demands for the Region, and the ease of meeting these from increased use of existing resources, the re-use of effluents is seen as inappropriate at this time. Should the Region’s resources become significantly more stressed in the future it may become necessary to investigate effluent re-use for resource augmentation. 5.7 ALTERNATIVE WATER SOURCES In addition to the options detailed above there are various alternative sources of water. An exhaustive list of such options has been examined on behalf of the NRA including desalination, transfers from Europe, a national water grid, transfer by ship and icebergs. These all proved to be either impractical, far more expensive than conventional schemes, or both. The only possible exception is desalination, if technological progress were to allow a substantial reduction in the cost and energy consumption. As the limited marginal demands identified in this study can all be satisfied by conventional schemes these ‘esoteric’ options are not considered further. 5.8 IMPACT OF BARRAGE DEVELOPMENTS Barrages are typically promoted for amenity or power generation purposes but may be specifically developed for the benefit of water resources. Barrage developments may require an impounding licence by virtue of the Water Resources Act 1991. Where there is an associated HEP scheme then an abstraction licence may also be needed. The impact and side effects of estuarine barrage construction can be both positive and negative in water resource terms. Barrages associated with HEP schemes can have major implications for development of upstream resources. If the configuration of the barrage means water is abstracted to pass through the turbines then upstream resources could be sterilised. The impounding effect of a barrage, with a water level retained higher than would always occur naturally, can be a net benefit to abstractors within an otherwise tidal reach. The fixed level, or higher mean level within the range, means that it is easier to create intakes, and water quality would be less variable. Exclusion of brackish or saline water by the barrage effectively moves the limit for abstraction to the barrage itself. The retention of a greater flow and level of fresh water within the river upstream may also be beneficial to the river. Depending upon residual flow requirements it may be possible to permit higher volumes of abstraction from within the ponded reach than if it were a free-flowing watercourse. By virtue of their location, barrages are likely to affect groundwater levels. The situation may be further affected by barrages within urban areas which create a rise in groundwater levels within made ground. Additionally, increased water levels may reduce the thickness of the unsaturated zone and its effective attenuating ability on leachate egress from older WRWRS.REP/75F/27 June 1994 Page 89 landfills which are operated on the principle of non-containment. If the unsaturated zone below contaminated ground becomes saturated this may cause mobilisation of contaminants which are currently in equilibrium with groundwater. Over the last forty years or so barrages have been proposed for abstraction on the estuaries of the Usk, Conwy, Dyfi, Mawddach, Taf and Tywi, and the Cleddau at Milford Haven. None of these proposals have gone ahead. Three barrage developments have been proposed in recent years for amenity - Swansea barrage on the Tawe estuary, Cardiff Bay barrage on the Taff and Ely estuaries, and Usk barrage on the Usk estuary. The Swansea Bay barrage was completed in 1992. The Cardiff Bay barrage received parliamentary approval in 1993. The Usk scheme is being actively promoted, although the NRA is concerned about its potential impact on the environment. The Swansea Bay barrage is subject to water quality and fisheries monitoring by NRA in order to assess the impact of the barrage. Initial results indicate pronounced saline stratification normally exists within the impoundment except under extreme high river flows. The NRA, in light of experience with the Swansea scheme, has agreed environmental safeguards with the developers of the Cardiff Bay barrage. These include a programme of water quality monitoring and maintenance of a specified minimum dissolved oxygen level, uprating of treatment of an industrial discharge, provision of a well-designed fish pass, and minimisation of saline intrusion. The NRA has also agreed a water budget with the developers to allow for competing demands that will safeguard the requirements of migrating salmonids. Additionally, extensive investigation of the impact of the barrage impoundment on groundwater levels in Cardiff has been undertaken and mitigation measures developed by the promoter to combat the rise in groundwater levels. The Usk barrage is currently being promoted by Newport Borough Council and Gwent County Council under an order under the Transport and Works Act 1992. The scheme involves a partial exclusion barrage which will be overtopped by 71% of tides in order to maintain water quality and allow flushing of downstream sediments. The Usk is an important salmon fishery and the fish pass will require careful design. The NRA is strongly opposed to this scheme on environmental grounds. Several sites in the Region have been put forward as potential sites for small-scale tidal power generation barrages. These are on the Dee estuary, Loughor estuary, Conwy estuary and at.Milford Haven. However, recent research (Ref 39) indicates that this form of power generation is not economically viable and tidal power barrage schemes are highly unlikely to go ahead. 5.9 POSSIBLE IMPACTS OF CLIMATE CHANGE ON WATER RESOURCES The water resources assessments detailed in this report make no allowance for the possibility of climate change. However, there is international concern that global warming will cause changes in climate which could have significant implications for water resources. The natural variability of rainfall means it will be many years before any underlying trend can be positively identified. It should be borne in mind that estimates of the impact of future climate change are at best only as reliable as the estimates of the size of the change itself. Recent research indicates that annual runoff could decrease by 10% to 30% in the driest scenario or increase by 17% to 30% in the wettest scenario (Ref 40). Under the UK Climate Change Impacts Review Group’s (CCIRG) ‘best estimate’ rainfall scenario for Page 90 WRWRS.REP/75F/27 June 1994 Britain in 2025 (a 2-4°C rise in mean surface temperatures and a small increase in rainfall; 8% in winter, no change in summer) average annual runoff was predicted to increase by up to 5% (for a 7% increase in PE) or decrease by 15% (for a 15% increase in PE) in the south and east of the UK (Ref 14). However, in the north and west of the UK - which includes the Welsh Region of the NRA - the predicted changes were smaller, a 5% increase and a 3% decrease respectively. Climate change is likely to accentuate the current wetter north and west and drier south and east, with summer runoff likely to be reduced and winter runoff increased. The majority of strategic resources in Welsh Region are located in upland catchments. The authors of Ref 14 postulate that in typical upland catchments summer runoff could decrease by 6%, with increases in the rest of the year of between 6% and 8%. Lower summer inflows would reduce available water during the critical period of reservoirs by up to several percent, with smaller reservoirs most affected. In lowland catchments the overall yield of sources would be expected to increase due to the greater winter inflows. Lowland rivers, additionally, have run of river direct abstraction schemes which are unsupported by storage. Most of these abstractions now have minimum flow conditions below which abstraction may no longer take place. The effect on water available would depend on the river flow, minimum flow conditions and the amount taken, and could vary from no effect to considerable effect. Preliminary results from research into possible impacts on water resources in Wales (Ref 41) confirm the above findings, identifying the smaller upland catchments and reservoirs in areas of lower rainfall as most vulnerable. Climate change may also lead to a rise in sea level. This may have lead to increased saline intrusion, and potentially could affect abstraction points near to tidal limits - CWC’s abstraction from the Dee at Chester (surface water), and Dwr Cymru’s abstractions at Pendine and Schwyll (groundwater). Clearly more research is needed on the likely effects of climate change on water resources. If the changes postulated under current ‘best estimates’ were to occur, then most reservoir sources in the Region are uniikely to be affected very much, with single season reservoir yields likely to reduce by less than 3%. However, when planning new sources each development should be studied individually using sensitivity analyses. WRWRS.REP/75F/27 June 1994 Page 91 6 PROPOSED REGIONAL WATER RESOURCES STRATEGY 6.1 INTRODUCTION The NRA is responsible for the management of water resources in England and Wales. As the Guardians of the Water Environment, the NRA is committed to ensuring that proper use is secured through a long term strategy which will sustain water resources for generations to come. The most appropriate approach towards sustaining a healthy water environment, as well as a socially acceptable balance between the environment and legitimate demands for water, comprises efficient use of water resources and environmental sensitivity. Overall, the strategy is guided by a balanced adoption of three fundamental principles - economic efficiency, environmental sustainability and precaution. In the preceding Sections the Region’s water resources and the demands upon them, both human and environmental, have been described. The future additional demands have been forecast and options for meeting them have been explored. A number of associated issues have also been identified. In normal years there is no real problem, given the water networks which have been built up over the years to meet the needs of the population. However, that population, its needs for water, and its environmental expectations are all rising, and plans must be prepared to meet these demands. This Section makes proposals for a framework for a Regional Water Resources Strategy in the form of proposed policies for water resources management and proposed extensions to the Region’s PWS network. 6.2 PROPOSED POLICIES FOR WATER RESOURCES MANAGEMENT 6.2.1 Licensing of abstractions Nearly all those who wish to abstract water from rivers and from aquifers require an abstraction licence from the NRA. This is one of the NRA’s key water resources activities. In determining any licence application the NRA should: * - take account of other uses within the catchment as identified through Catchment Management Plans; * consider the effects on other abstractors: abstractions should not be allowed that would derogate existing licence rights and other protected rights to abstract unless suitable arrangements are agreed: * consider the overall availability of water; ensure the abstraction will not be in excess of the renewable resource; * consider the impact on river flows, especially ensuring flows are not reduced to unacceptably low levels; * consider the potential effect on wetlands and pools, and not allow abstractions which would be damaging or otherwise unacceptably affect them; and Page 92 WRWRS.REP/75F/27 June 1994 * advise the applicant in general terms on the availability of water, the likely consequences and constraints which would have to be attached to the abstraction, and how reliable it might therefore be. Knowledge of the available surface water and groundwater resources is fundamental to ensuring reasonable needs are met in a sustainable, environmentally acceptable, manner. The NRA is currently undertaking a project to develop a regional licensing policy. As part of the project a methodology will be formulated for the assessment of catchment resources. Once the regional licensing policy is developed the NRA will need to assess resource allocation in catchments and determine the need for revocation and/or reduction in licensed quantities. A large part of the Region in Western Wales is exempt from licensing for groundwater abstraction. However, there are believed to be regionally significant groundwater resources in this area and it is recommended that, in keeping with the NRA’s water resources obligations, the NRA looks into the possibility of abstractions over a threshold being subject to licensing legislation. 6.2.2 Demand management The NRA should continue to advocate demand management by all water users to the extent that it is economically justified. Before any new sources are developed, the NRA should ensure the water companies are doing all they can to reduce leakage and to carry out effective demand management. Selective domestic metering, with an appropriate tariff, is to be encouraged in areas where resources are stressed. 6.2.3 The reallocation of water In order to ensure resources are used wisely the NRA needs to assess whether abstractions are reasonably required. The analysis of water usage carried out for this project has highlighted the fact that actual demands of industrial users are significantly lower than licensed abstraction. It is therefore recommended that the NRA investigates reduction in authorised quantities where there is no need for the original licensed quantities and revokes licences that have not been utilised for over 7 years. Also, the NRA should investigate the scope.for tradeable permits and for incentive charging, as means of releasing entitlements to abstract water for relatively low value uses. 6.3 PROPOSED EXTENSIONS TO THE PUBLIC WATER SUPPLY NETWORK In Section 4 the marginal demands for PWS were forecast for a range of scenarios incorporating different assumptions about demand management, per capita consumption and commercial growth. Deficits range from a regional total of 17 Ml/d in 2021 for the low growth scenario to just under 100 Ml/d in 2021 for a high growth scenario. The high forecast combines relatively large increases in domestic and industrial consumption with no improvements in leakage control or increase in metering. The medium growth forecast has only a small increase in domestic and industrial consumption, accompanied by an increase in metering and significant reductions in leakage. However, notwithstanding the benefits offered by improved leakage control some new developments are needed to meet deficits. The low growth forecast assumes a very modest increase in domestic demand, no net increase in industrial consumption, but very tight WRWRS.REP/75F/27 June 1994 Page 93 control of leakage (principally by Dwr Cymru). Whilst it is recommended that the NRA continues to press all the water companies for effective demand management, it is likely that actual change in demand will lie somewhere between the low and medium growth forecasts. 6.3.1 Medium growth scenario The following sequence of development is proposed to meet the marginal demands arising under the medium growth forecast, based on the review of options for making more water available. i) From 1996 Dwr Cymru to phase in local source developments in Hereford and Radnor (Option 1), North Dyfed (Option 2) and Meirionnydd (Option 3) to meet the small deficits in the Company’s South East Division, South West Division and North East Division. The 10.6 Ml/d deficit in the South West Division (Ystradfellte supply zone) commencing in 1996 to be met from the 63 Ml/d surplus in the adjacent Felindre/Schywll supply zone using existing trunk mains. ii) From 2006 CWC’s deficit to be met from increased abstraction at Barrel well Hill from the River Dee with stepped increases in their licence. iii) From 2011 WEDWC’s deficit to be met by increased abstraction at Bangor on Dee from the River Dee with stepped increase in their licences. The total marginal demand on the River Dee system in 2021 will be 13.2 Ml/d (commencing in 2006). This deficit to be met by raising the crest of Llyn Celyn Yield 20 - 25 Ml/d (Option 6). 6.3.2 High growth scenario Should PWS demand grow in line with the high growth forecast then the following sequence of development is recommended i) From 1996 Dwr Cymru to phase in local source developments in Hereford & Radnor (Option 1), north Dyfed (Option 2) and Meirionnydd (Option 3) to meet the . small deficits in the Company’s South East Division, South West Division and North East Division. ii) From 2001 CW C’s deficit to be met from increased abstraction at Barrel well Hill from the River Dee with stepped increases in their licence. iii) From 2006 WEDWC’s deficit to be met by increased abstraction Bangor on Dee from the River Dee with stepped increase in their licences. Dwr Cymru also to increase abstraction from the Dee at Poulton with stepped increase in their licence. iv) From 2011 Dwr Cymru to meet the deficit of 3.5 Ml/d in the Cowlyd supply zone in the North East Division by increasing the direct supply yield of Cowlyd reservoir (Option 4). This is the only new resource development required in North Wales to meet regional demands. Page 94 WRWRS. REP/75F/27 June 1994 v) From 2016 Dwr Cymru to meet the 25 Ml/d deficit in the South West Division using the uncommitted licensed yield of 25 Ml/d in the regulated River Tywi (the surplus in the Felindre/Schywll supply zone) as follows:- 1. Implement the River Tywi to Pembrokeshire transfer scheme (Option 11), supplementing local source development, to meet the deficit of 10.7 Ml/d in the Pembrokeshire supply zone; 2. The notional deficit of 14.5 Ml/d in the Ystradfellte supply zone to be met from the adjacent Felindre/Schywll supply zone using existing trunk mains. Also from 2016, Dwr Cymru to meet the 37 Ml/d deficit in the South East Division from existing sources in the South West Division by one of following means:- 1. Recommission the Schwyll source (to be mothballed in 1995 and excluded from available yield in Division). Option 13 - Yield 22 Ml/d; Raise the top water level of Llyn Brianne by 2m (Option 8); and Construct the pumped River Tywi to River Usk transfer and operate at 15 Ml/d (Option 9). 2. Construct the gravity River Tywi to River Usk transfer scheme (Option 10). The total marginal demand on the Dee in 2021 will be 28.4 Ml/d commencing in 2001. This deficit can be met by construction of some or all of the works detailed in Section 5.4.3.1 ie. Option 5 - Pumping station to transfer surplus water from Llyn Alwen to Llyn Brenig (Yield 1 5 -2 0 Ml/d); Option 6 - Raise the crest of Llyn Celyn (Yield 20 - 25 Ml/d). 6.4 PRIVATE ABSTRACTIONS The only private demands forecast to increase above current licensed quantity are for spray irrigation and HEP. HEP and fish farming are large legitimate uses of water which do not consume resources. Both of these uses can need reservation of large quantities of water and so can impose a constraint upon water available to others upstream. The main issues involved largely relate to the ‘no-derogation’ principle. This is because licensing legislation does not allow new abstractions to use water that has been reserved in a licence downstream. Non-consumptive type uses are often located in the lower reaches of catchments and where there is limited scope for the re-use of water when returned. To avoid sterilising the tuture use of upstream resources when considering new licences of this type it is recommended that the NRA seeks to negotiate a quantity for other future potential uses as it is unlikely that such a reservation would have a significant impact on the viability of schemes, especially HEP, which will mainly depend on the availability of the higher winter flows. In many cases licences should be time limited to allow periodic review of licence conditions. In some cases licences that are already held may not be appropriate for current use, as circumstances have changed, for example in industry. But, their existence prevents the issue of licences to others. Licences should be reviewed if resources are to be fairly allocated. This information would be required in support of the abstraction licence application. WRWRS.REP/75F/27 June 1994 Page 95 The nature of HEP installations often means there are other issues specific to this category of use. They can cause extreme and often unacceptable fluctuations in flows downstream with impacts on water quality and fisheries. This is particularly so where minimum flows downstream are important for dilution of effluents and protection of fisheries. In some cases it may be necessary for an environmental appraisal to be carried out by the promoter of the scheme including proper consultation with relevant outside bodies and organisations. It may be that the impact of schemes for HEP, fisheries, etc can be overcome by the way in which they are operated. How schemes are operated can be incorporated into agreements associated with licences. 6.4.1 Spray irrigation The availability of water for spray irrigation is inevitably limited at critical times as peak demands will coincide with the lowest river flows. Any investment in both local and strategic resources for agricultural uses could be funded from within the industry, just as the water companies secure their resources by capital investment. A contribution to the cost of developments may be appropriate where schemes incorporate significant environmental gains alongside resource enhancement. The NRA could act as a facilitator, exploring any new initiatives proposed within the constraints of current legislation governing licensing. Hopefully research will continue into more efficient irrigation practices and new farming methods which help conserve available soil moisture and the development of drought resistant strains of crops will help better use of available water resources. 6.4.1.1 Management initiatives Scheduling systems designed to optimise the application and phasing of irrigation to match the specific needs of the crop are widely used. This could be assisted by the use of data loggers. These provide detailed information on water use, and can assist farmers in future management decisions and improve the efficiency of water usage on the farm. The NRA could advise on installation and processing data. Actual water use averages only 40% - 60% of licensed quantity (see Appendix D) in many years. This reflects a contingency element, but also the variance in the needs of many individual farmers due to crop rotation practice. Arrangements for pooling and sharing water already licensed may enable a better and fairer allocation. Where individual farmers have licences for both surface water and groundwater sources there is often scope to operate them conjunctively. This can increase the yield of water available to the farmers, especially where low river flows are a constraint, and can also frequently offer opportunities that are __ environmentally beneficial. This conjunctive use principle applies also to multiple farm situations. Where low flow restrictions on licences can present difficult operational limitations on some farmers others may be in a position to overcome these restrictions by making compensatory discharges from groundwater resources elsewhere in the local system. This would for the most part be the subject of commercial arrangement between the parties, but the NRA would have to be satisfied that the wider needs of the environment are fully met and the schemes can operate within the licensing framework. Page 96 WRWRS.REP/75F/27 June 1994 6.4.1.2 Development initiatives Conjunctive use schemes can optimise resources, but the storage of winter water is the only true means of enhancing and securing resources at critical times. These local developments are assumed to be sufficient to meet increases in demand for irrigation water. Where individual farmers view reservoir construction as uneconomic, it is possible to reduce unit costs by co-operative ventures by economy of scale. Distribution difficulties can be a problem for strategically placed local reservoirs. However, the NRA should consider schemes which allow the continuation of an otherwise low flow restricted abstraction at one location if offset by compensatory discharges elsewhere. For example, from reservoir storage. 6.5 RECOMMENDED AREAS OF FURTHER WORK The following recommendations are made with regard to areas where work is required to gain additional information of assistance in water resources planning for the Region:- i) Licence and consents databases - This project has highlighted a lack of consistency in both databases. It is recommended that the NRA undertakes an audit of the two systems. ii) Abstraction returns - Analysis of the returns data on the licence database has shown it to be incomplete, with only about 50% of the licensed quantity accounted for. In order to improve the reliability of estimates of actual water usage it is recommended that the NRA collects together available returns data and updates the database. iii) Groundwater resources - The exact size of the Region’s groundwater resources is not currently known. However, significant demands are made of these resources. It is recommended that the NRA undertakes a detailed assessment of the long term rate of recharge to the Region’s groundwater management units and evaluates the acceptable degree of development. The regional licensing policy should be extended to include provisions for licensing of groundwater abstractions. iv) . Licence-exempt areas - The management of water resources can only be hampered by the existence of large licence-exempt areas in the Region. Whilst resources and demands are probably relatively small in size it is recommended that the NRA investigates the practicalities of removal of licence exemption for larger abstractions. v) Naturalised flows - The relative abundance of water in the Region has resulted in there being very few naturalised flow records in the Region. As naturalised flows can provide valuable information of assistance in evaluating environmentally acceptable flows in rivers it is recommended that the NRA investigates the possibility of a programme of naturalisation. WRWRS. REP/75F/27 June 1994 Page 97 REFERENCES 1 Water Resources Act 1991. London: HMSO, 1991. 2 INSTITUTE OF HYDROLOGY and BRITISH GEOLOGICAL SURVEY. Hydrological Data UK - Hydrometric Register and Statistics 1986-1990. Natural Environment Research Council, 1993. 3 NATIONAL RIVERS AUTHORITY. Demands & Resources o f Water Undertakers in England & Wales - Preliminary Report Under Section 143(2)(a) Water Act 1989. 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Impact o f Climate Change on River Flow Regimes in the UK. J. Inst. Wat & Envir. Mangt, 1992. Vol. 6, pp. 432-442. 41 H OLT, C.P. and JONES. J.A.A.. Potential Impact o f Global Warming on Water Resource Management in Upland Wales. Proceedings ofthe 4th National Hydrology Symposium. London: Institute of Hydrology, 1993. Page 100 WRWRS. REP/75F/27 June 1994 BIBLIOGRAPHY BINNIE & PARTNERS. Report on Vyrnwy Resource Study. B&P, 1993. CHESHIRE COUNTY COUNCIL. Cheshire Replacement Structure Plan - Explanatory Memorandum, Cheshire 2001. CCC, 1992. CLWYD COUNTY COUNCIL. Clwyd Structure Plan: 1st Alteration (Policy & Explanatory Memorandum). CCC, 1991. COUNTY OF SOUTH GLAMORGAN. Structure Plan Proposed Alterations - Written Statement. CSG, 1985. DWR CYMRU. Eryri/Ynys Mdn water supplies - A review following deferment o f the Cowlyd-Ogwen Scheme. DC, 1986. DYFED COUNTY COUNCIL. Dyfed Structure Plan (including Alterations No.l). DCC, 1990. GLOUCESTERSHIRE COUNTY COUNCIL. Structure Plan (1st alteration) - Explanatory Memorandum. GCC, 1992. GLOUCESTERSHIRE COUNTY COUNCIL. Structure Plan - 2nd Review 1991-2011 Project brief GCC, 1992. GWYNEDD COUNTY COUNCIL. Statistical Review. GCC, 1993. GWENT COUNTY COUNCIL. Gwent Structure Plan - Approved Plan (Incorporating 1st & 2nd alterations). GCC, 1990. GWENT COUNTY COUNCIL. Gwent Structure Plan 1991 - 2006 (Proposed amendments to deposit Plan). GCC, 1993. HEREFORD & WORCESTER COUNTY COUNCIL. Structure Plan 1986 - 2001. HCC, 1993. HOWARD HUMPHREYS CONSULTING ENGINEERS. NRA National Water Resources Strategy- Strategic Environmental Assessment. Final Report (draft). HH, 1993. JONES, F.H.. Barrage Developments in the Welsh Region: The Role of the NRA in Protecting the Aquatic Environment. Proceedings of IWEM Meeting - Barrages For Regeneration. 1993. JONES. K.. Regeneration o f Swansea. Proceedings of IWEM Meeting - Barrages For Regeneration. 1993. LAMBERT. A. Regulation o f the River Dee. Regulated rivers: Research and management, 1988. Vol. 2, pp. 293-308. MID GLAMORGAN COUNTY COUNCIL. Mid Glamorgan County Structure Plan - Approved Plan (in corporati ng Proposals for A Iteration No.l). MGCC, 1989. MID GLAMORGAN COUNTY COUNCIL. Mid Glamorgan County Structure Plan - Draft Replacement Structure Plan. MGCC, 1992. WRWRS.REP/75F/27 June 1994 Page 101 NATIONAL RIVERS AUTHORITY. A Water Resources Development Strategy for England and Wales. 2nd Draft. NRA, 1993. NATIONAL RIVERS AUTHORITY. NRA Water Resources Strategy. NRA, 1993. NATIONAL RIVERS AUTHORITY. The Quality o f Rivers, Canals and Estuaries in England & Wales - Report of the 1990 Survey. NRA, 1991. NATIONAL RIVERS AUTHORITY (Welsh Region). Upper Wye Catchment Management Plan - Consultation Report. NRA, 1993. NATIONAL RIVERS AUTHORITY (Welsh Region). River Conwy Catchment Management Plan - Consultation Report. NRA, 1993. NATIONAL RIVERS AUTHORITY (Welsh Region). Menai Strait Catchment Management Plan - Consultation Report. NRA, 1993. POWYS COUNTY COUNCIL. Powys County Structure Plan -1 st Alteration (Written Statement and Explanatory Memorandum, Consultation Draft. PCC, 1992. PRICE, J. OFWAT Research Paper No. 1 - Comparing the Cost o f Water Delivered. OFWAT, 1993. REES, J.A., WILLIAMS, S., ATKINS, J.P.. HAMMOND, C.J. and TROTTER, S.D.. Economics of Water Resources Management. NRA R&D Project 248. NRA, 1993. ROSCOE, R.S. and HUNTER, P.D.. The Cardiff Bay Barrage. Proceedings of IWEM Meeting - Barrages For Regeneration. 1993. SHROPSHIRE COUNTY COUNCIL. Shropshire Structure Plan 1989-2006 - Explanatory Memorandum. SCC, 1993. SIR ALEXANDER GIBBS & PARTNERS. Cowlyd - Ogwen Diversion. Reconnaissance Report. Welsh National Water Development Authority, 1977. SOUTH GLAMORGAN COUNTY COUNCIL. South Glamorgan Structure Plan - Approved Structure Plan Policies. SGCC, 1989. WATER SERVICES ASSOCIATION & WATER COMPANIES ASSOCIATION LEAKAGE CONTROL STEERING GROUP. Measurement and Control o f Distribution Losses - Glossary of Terms (Section A). Working Draft 2.5. WSA, 1992. WELSH TOURIST BOARP. Tourism 2000 - A Strategy for Wales. Draft Report for consultation. WTB, 1993. WELSH WATER AUTHORITY. Ogwen abstraction scheme. Technical Report - Part 1. WWA, 1982. WEST GLAMORGAN COUNTY COUNCIL. West Glamorgan Structure Plan - Alteration No.l, Written Statement and Explanatory Memorandum. WGCC, 1988. WEST GLAMORGAN COUNTY COUNCIL. West Glamorgan Structure Plan Review No.2 -Draft Replacement Plan (Pre-Deposit Consultation). WGCC, 1993. Page 102 WRWRS.REP/75F/27 June 1994 APPENDIX A TERMS OF REFERENCE WRWRS.REP/75F/27 June 1994 NATIONAL RIVERS AUTHORITY WELSH REGION WATER RESOURCES DEVELOPMENT STRATEGY 1. OBJECTIVES 1.1 The National Rivers Authority (NRA) is required under Section 143 of the Water Act 1989 to "...collate and publish information from which assessments can be made of the actual and prospective demand for water, and of actual and prospective water resources, in England and Wales". 1.2 The objective of this Consultancy Project is to carry out this Statutory requirement through the production of a Welsh NRA Regional Water Resources Planning and Development Strategy. 2. SPECIFIC OBJECTIVES 2.1 Review the current development of water resources within NRA Welsh Region and their use in meeting existing demands for water. 2.2 Collate and review estimates of future demands for Public Water Supply abstraction in the Region up to the year 2021, in 5 year steps, commencing 1981., 2.3 Collate and review estimates of future demand for all other water requirements which impact on the resources of the Region (including those from outside the Region) up to the year 2021, in 5 year steps, commencing 1981. 2.4 Consider the scope and options available to formulate a sustainable policy. Provide a plan for developing and augmenting water resources, and ensuring their proper use, to meet existing and estimated future demands for water in Welsh Region to 2021. 2.5 Compare the various options and proposals considered, take account of environmental impact and other relevant criteria, and give due weight to economic considerations. 2.6 Liaise with the Consultants undertaking the National Water Resources Development Strategy to provide Welsh Region input as necessary and ensure compatible development so far as is possible. 2 . 7 Take account of .progress made on the NRA Welsh Region proposed Abstraction Licensing Policy and other associated National and Regional developments. 2.8 Hold monthly progress mee tings be tween the Consultant's project Manager and the NRA's Project Leader, with other staff from both sides as appropriate. Submit a draft version of the final report one month before the final report is due. 2.9 Complete project before 15th February 1994. 3. BACKGROUND The Welsh Region of the NRA has more rainfall Chan any of the English Regions; 1350 mm on average. Of this, just under half evaporates leaving the remainder to sustain rivers and groundwaters and provide all the water requirements of the Region. This accounts for 26% of the total available water resource of the NRA's Regions. The Welsh Region has mountainous terrain, thin soil coverage and limited aquifers. Rainfall therefore finds its way quickly to the sea and little is held back to provide baseflow to sustain river flows during dry periods. The Region's river flows therefore rise and fall quickly in response to rainfall. Historically, lack of local sources for public water supply in the industrialised Midlands and North West England, as well as South East and North East Wales, led to the development of direct supply reservoirs in the sparsely populated uplands of Wales, such as the Elan and Taf Fawr/Fechan Valleys. More recently this development has continued, but with river regulation reservoirs replacing direct supply as a more efficient way of utilising resources e.g. Llyn Brianne on the Tywi, and Llyn Celyn and Llyn Brenig on the Dee. Industrial and agricultural abstractions are important. More recently industrial abstraction has declined with the collapse of "heavy" industry. However, the impact of these abstractions has been replaced by the growth in hydroelectric generation and agricultural spray irrigation. The Welsh Region controls over 4,300 abstraction licences, the majority of which are for minor agricultural and domestic supplies. The total licensed abstraction is 24,200 Megalitres per day (Ml/d) from non tidal surface and groundwaters. This is equivalent to BOX of the average daily available water of the Region, or 97% during the 1 in 50 year drought. However, by far the greatest volume licensed is for non - consumptive hydroelectric generation (57%). Spray irrigation by contrast is almost totally consumptive and, even though quantities licensed are small by comparison (less than 1%), abstraction can have a dramatic effect on summer river flows. The largest "loss" of water in Welsh Region arises from public water supply (PWS). Welsh Region is a major exporter of water; a third of licensed PWS abstraction is used outside the Region, and even within the Region almost half of PWS returns are discharged directly to tidal waters. As a result only a third of the 3,627 Ml/d licensed for PWS abstraction is returned to the Region's rivers. 4. DEMAND FORECASTS The discussion document "Water Resources Development Strategy" published by the NRA in March 1992 identified an 8% growth in PWS requirements to 2021. If correct this would still give a surplus of 25% more water resources in Welsh Region than demand required. However, these data apply to the whole of the Region and mask local deficits and surpluses. For example, the Dee catchment provides water locally and for export to the North West of England. This is achieved through a number of large regulating reservoirs controlling river flows. Abstractions and environmental consideration are catered for by reservoir releases when natural river flows are too low. Despite the size of this scheme, it is estimated that the surplus yield in the system will be utilised by early next century. To meet predicted demands therefore further enhancements of the current system may be required. This study is required both to plan the future development of resources to meet Regional requirements and to feed data into the National Strategy. STRATEGY 5.1 METHOD The study will be carried out making best use of available data. Thus, a main task will be to collect and collate existing work on demand forecasting and resource planning, as well as information on the yield, performance and distribution system constraints of existing sources, and best use practices. The review would be based principally on information and data provided to the Consultants by the NRA, Water Companies, major industrial users and agricultural information sources. The successful Consultant would be expected to work with external organisations in order to establish existing and future demands. These would include the demands both of abstractors and the aquatic environment. All data and assessments should be broken down to a sub-catchment level where possible and practicable. 5.2 PRESENT RESOURCE/DEMAND BALANCE : a. Identify and quantify the uses of water abstracted within Welsh Region. b. Identify and quantify the imports/exports of water into/out of Welsh Region. c. Compare current licensed quantities with actual abstraction and published yields. d. Present information on the broad categories of use within the Region (See Appendix 1), including estimates of total abstraction, nett abstraction, re-use, discharges to tidal waters, and inter-basin transfers. A breakdown between surface water and groundwater should be included. Any tidal water abstraction should be noted. e. Take account of source yields and performance as currently understood by the operators, providing where possible, the definitions used. Seek to place all yield information on a broadly comparable basis. f. Evaluate constraints on yield such as treatability, treatment works capacity, raw water quality, OFWAT guidelines on Levels of Service Indicators, river flow, required flow to estuaries, adverse environmental impact and operating rules. g. Where practicable, identify current sources which will close or be mothballed due to economic constraints brought about by failure to meet quality objectives. h. Review all existing sources, including multi - use/conjunctive use schemes, and comment on efficiency and proper use of the resources. Propose alternative more effective and/or efficient methods of operation or improvements which should be further investigated. Provide preliminary resource values, engineering and economic feasibility , and environmental e ffects . i. Note the distribution system into which each source feeds, insofar ;is this may govern source utilisation. Provide maps of distribution systems and supply zones. 5.3 FUTURE DEMANDS FOR WATER SUPPLY a. Review the methodology by which future demand patterns have been formulated, and comment on their validity. b . Make forecasts at a sub-catchment level where possible of nett: abstractions for industry and agriculture, including spray irrigation for every 5 years from 1981 to 2021. Special account should be taken of : o - Hydroelectric industry (HEP) : This relates to potential growth of this form of energy production and the impact such abstractions have on potential abstraction upstream of the HEP site. o - Spray Irrigation (SI) : The NRA R & D project B03 413 - "Demand for Irrigation Water" should be used as a basis for predicting the future requirements for SI. Average year and drought year SI demand for different crop types should be considered. These should be identified at a subcatchment level. c. Make forecasts of nett abstractions for Public Water Supply. Forecasts for PWS should be at Company level for abstractions used outside the Welsh Region. For those areas within the Region, details should be provided at supply/demand zone levels; the smallest managed areas. Demand forecasts should be compiled using principal components of use. Guidance on this is provided in Appendix II. Special account should be taken of : o - Tourism : Due to its importance in Wales, estimates of seasonal demand should be identified. This may be done through occupancy data and caravan park registers. Contact should be made with the Welsh Tourist Board and other interested parties. This will assist in the production of Peak and Average demands for supply zones. o - Housing : Forecasts of housing development, house occupancy rates and percentage of housholds connected to mains water should be identified. o - Metering : The take up rate of metering and its impact on demand should be addressed. To assist this records of historic metered customers should be compiled. d. Reliability of PWS should be assessed using the current OFWAT guidelines for standards of service. Source yields should take these into account. e. Considerable advantage is seen in making alternative higher and lower trend forecasts to produce a future demand envelope. This would make it possible to test the robustness/sensitivity and also the timing of potential solutions for meeting the range of demands postulated. f. The forecasts obtained in b. to f. above should be collated and reviewed Co identify the catchments and/or supply zones, use categories, nett c.all on resources, date Che forecast relates to and whether high or low trend. Data should be presented in numeric and graphical form. g. The aim is to present broadly consistent demand forecasts relevant to resource use and development. h. From the foregoing collation of future demand esCiinaCes/trends, che Consultant will be required to deduce the resulting deficiency of : (a) existing abstraction and (b) resource capability in meeting such future demands, such as source life expectancy, and reduced/increased yields (due to afforestation, siltation, deteriorating quality, enhanced legislative constraints and improved treatment methods.) and thus derive the scale of resource development, redeployment and efficiency steps required to meet estimated future demands. 5.4 REVIEW OF OPTIONS FOR FUTURE STRATEGY : a. The Consultant will be required to identify and review various potential options for meeting the deficiencies recognised above. The NRA will advise on future water resources development considered to date. b. The yield for potential schemes should be identified on a consistent basis. For surface sources these should be based on a 1 year in 50 drought severity, linked to the current OFWAT guidelines on Levels of Service Indicators. c. Options will be reviewed with Water Companies, major industrial customers and agricultural bodies as appropriate. Their views, as our customers, are an important part of this Strategy. Regional NRA operations staff will also be formally consulted at this stage. d. Inter-Basin transfers would be applicable where resource capacity, water quality, environmental and/or economic considerations appeared to favour transfers from areas with existing or potential surplus water resources capacity. e. Consider the elements of demand management (eg. Leakage/waste reduction, increased re-use/recycled water effluent, tariff structuring, monitoring and metering), likely to be most effective and viable. Identify what are reasonable "economic levels" of leakage on a sub - regional basis. Consider the extent to which feasible and cost-effective demand management may help in closing or extending the output/demand balance. All reference to, and assessment of, demand management should be based on the latest methods and terminology arising from the Water Industry's 'National Leakage Control Initiative'. f. Consider the scope for further development of groundwater throughout the Region in the light of constraints relating to natural recharge, environmental consequences of abstraction and water quality for use as water supply. This should be reported on an identifiable groundwater unit basis. g. Consider further interlinking and conjunctive use scheme developments where yields and/or environmental factors will benefit. h. Consider use of sewage effluent as a water resource. Propose Regional policy on dealing with this issue, which takes into account water quality issues, medical aspects, and discharge locations. Identify locations where additional resources may be viable. i. Review the possibility of "alternative" sources of water in the context of Welsh Region demand, or as means of providing additional resources for export. j . Consider the benefits or adverse impacts to water resources of existing and proposed barrage developments (e.g. downstream location of PWS intakes). Review and update the likelihood of estuary storage developments . 5 ENVIRONMENTAL CONSIDERATIONS AND ECONOMIC/COST ASSESSMENT Review environmental requirements and constraints on the various options and proposals to ensure that :- o - significant environmental constraints are identified at an early stage. o - environmental considerations are assessed on an equal basis with other factors. The exercise should be limited to discussions with NRA Regional staff concerned with environmental quality, fisheries, recreation and conservation, together if necessary with consultation with other parties on specific proposals if so agreed with the NRA. Environmental aspects will interlink with the Region's Abstraction Licensing Policy study. This will cover minimum residual flows; flows to estuaries; effects of abstraction on river water quality; environmental impact constraints on resource development; fisheries, conservation, recreation, amenity and navigation impacts. The possible impact of climatic change on water resource availability should be explored. Consider both Capital and Running costs of all proposed schemes. This should be achieved on a consistent basis to provide appropriate cost estimates for comparison of options, rather than specific accuracy and precision. The WRc Technical Report on Costs and Rates for the UK Water Industry should be used where relevant. Provide recommendations. 6. RELATED PROJECTS. The Consultant will be expected to keep up to date with the development of other related projects which impinge on the Regional Strategy. These include o - NRA R & D Project B02 282 "Environmentally Acceptable Flows", o - NRA R & D Project B03 248 "Economic Effects of Water Resource Managment". o - NRA R & D Project B03 414 "Surface Water Yield Assessment", o - NRA R & D Project B03 413 "Demand for Irrigation Water", o - NRA R & D Project B03 004 "Defining the Proper Use of Water Resources ". o - NRA - National Water Resources Development Strategy, o - National Leakage Control Initiative publications. o - Code Of Practice for the Measurement and Control of Distribution Losses - Leakage Control Steering Group Project, o - NRA Policy Guidance Notes, o - NRA Catchment Managment Plans. 7. MONITORING Monthly meetings to be held with Project Leader to monitor progress. Other meetings will be held on an 'As Needs' basis. 8. DISSEMINATION This study will form the basis of a strategy for the long term development of Water Resources in the Welsh Region of the NRA. The study will provide a number of outputs :- a. A Report containing all the detailed analysis; for internal use only. b. A "Public" Report containing detailed analysis as 'a' above; but excluding confidentially sensitive information. c. A bilingual * (English and Welsh) Consultation Document summarising the main results of the study and outlining possible options for future development. This will be produced for internal and external circulation and comment and should follow a similar format to the "Water Resources Development Strategy" discussion document published by the NRA ir. March 1992. d. Bilingual Overheads/Slides to allow promulgation of the results of the study, through talks, presentations etc., both within the NRA and to outside audiences. e. A bilingual summary Water Resources information leaflet. f. Cartographic output of demand zones and supply networks. NRA will provide the facility for translation. 9. TARGET AND TIMESCALE Project to be completed by 15th February 1994. 10. OUTPUTS a. Detailed Report 20 Copies plus disk containing text. b. Public Report 10 Copies plus disk containing text. c. Consultation Document Typeset on disk and hard copy (English & Welsh) d. Presentation Material Overheads/Slides. (English & Welsh) e. Information Leaflet Typeset on disk and hard copy (English & Welsh) f. Maps Four Copies of each. 11. COST As this contract is to be awarded through competitive tender, the cost will depend on the bids. It is the standard practice of the NRA that the contract will be awarded to the lowest tender unless there is good reason not to do so. The proposed method of payment will be negotiated on letting of the contract to the successful consultant. RAV 8/4/93 APPENDIX 1 USE CATEGORIES The following categories are to be split into surface and groundwater. Tidal should also be noted. WATER SUPPLY * PUBLIC WATER SUPPLY - PRIVATE INDUSTRY ELECTRICITY - COOLING HYDROELECTRICITY AGRICULTURAL - EXCLUDING SPRAY IRRIGATION SPRAY IRRIGATION FISH FARMING AMENITY / CONSERVATION OTHER APPENDIX II DEMAND FORECASTS OF PUBLIC WATER SUPPLY. General The NRA will provide population data at County, District and Community/Parish level, sourced from OPCS, Welsh Office and County Councils. The Community/Parish should be used as the building block to construct supply and demand zones. All information gathered in producing demand forecasts should be made available to the NRA in a structured format on completion of the project. Components of Demand Demand should be built up from its component parts ; household unmetered consumption, household metered consumption, industrial and commercial metered consumption industrial and commercial unmetered consumption unaccounted for water. Household Unmetered Supplies Definitions of this will be supplied. Consumption rates per capita or per household should be based where possible on property type water use data, such as the ACORN classification. Household Metered Definitions of this will be supplied. Consumption rates per capita or per household will be modified by a factor derived from the measurements of consumption in the National Metering Trials. Industrial and Commercial Metered Supplies. These should be estimated from the Water Company's billing records, with other known industrial developments taken into account. Further detail on the methodology will be supplied. Industrial and Commercial Unmetered Supplies These should be estimated from the Company's records, with the Company's metering policy taken into account. Unaccounted For Water Further detail on this subject and the methodology to be applied will be supplied. APPENDIX B THE GEOLOGY OF THE REGION WRWRS.REP/75F/27 June 1994 I APPENDIX C LICENSED ABSTRACTIONS IN SUB-CATCHMENTS WRWRS. REP/75F/27 June 1994 •Table C.1 Licensed abstraction from groundwater in the Region in 1993 (Daily average Ml/d) Subcatchment Use 1 2 3 4 5 6 7 8 9 10 11 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 ft 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.2 1.3 11.6 0.2 3.6 0.0 0.7 0.0 0.0 0.0 0.0 0.2 2.2 32.4 0.3 14.9 0.0 0.0 0.0 0.0 0.3 4.6 0.0 0.3 18.2 0.1 1.2 0.0 0.0 0.0 0.0 0.0 5.1 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.3 0.0 0.5 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 . 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.6 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 1.2 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.2 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.4 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 3.6 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.2 0.6 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 M M H M M M i 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 WMMMKkm 0.0 0.5 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.2 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 )Uppe>-Tywi'X>. >: 0.0 0.3 0.7 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 IWfJb*'... 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 wM*' * -#v'v 0.0 0.0 0.0 0.0 0.9 0.0 0.0 0.0 0.0 0.0 0.0 /Qower. >'V/Vm, ■' 0.0 0.2 2.4 0.0 1.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.0 0.9 0.0 0.0 0.0 0.0 0.0 0.0 llirt# . s . " ' . i 0.0 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Neath 0.0 0.0 0.0 0.0 0.1 0.0 0.0 0.0 0.0 0.0 0.0 Afan, Kenfig 0.0 0.0 0.0 0.0 1.6 0.0 0.0 0.0 0.0 0.0 0.0 Ogmore 0.0 0.0 27.9 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Thaw 0.0 0.2 7.2 0.0 0.4 0.0 0.0 0.0 0.0 0.0 0.0 Ely 0.0 0.0 0.0 0.0 8.0 0.0 1.0 0.0 0.0 0.0 0.0 Taff 0.0 0.0 0.6 0.0 6.8 0.0 0.2 0.0 0.0 0.0 0.0 Rhymney 0.0 0.0 0.0 0.0 3.1 0.0 0.0 0.0 0.0 0.0 0.0 Ebbw 0.0 0.0 7.4 0.0 6.3 0.0 0.0 0.0 0.0 0.0 0.0 Upper Usk 0.0 0.1 18.0 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Lower Usk 0.1 0.4 21.8 0.3 0.4 0.0 0.0 0.0 0.0 0.0 0.4 Upper Wye 0.0 0.5 1.7 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Lower Wye 1.2 2.7 31.6 0.2 0.3 0.0 0.0 0.0 0.0 0.0 0.0 Lygg 0.6 4.8 11.4 0.1 21.3 0.0 0.0 0.0 0.1 0.2 0.0 Monnow 0.1 0.9 4.7 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 USE TOTAL 3 15 204 2 72 0 2 0 0 1 10 Whole or part of subcatchment licence-exempt Categories of use 1 Spray irrigation 2 Agriculture 3 Public water supply 4 Private water supply 5 Industrial 6 HEP 7 Fishfarming 8 Electricity-cooling 9 Amenity/Conservation 10 Others 11 Transfers C:\JOBS\4432\SUMANALL.wk 1 C1 1 4 -J u n - T a b le C.2 Licensed abstraction from surface water in Welsh Region in 1993 — excluding tidal abstractions (Daily average Ml/d) Subcatchment Use 1 2 3 4 5 6 7 8 9 10 11 Anglesey 0.0 0.0 38.6 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Upper Dee 0.0 0.0 50.3 0.0 0.4 388.4 13.7 0.0 0.6 0.0 1245.7 Middle Dee 1.2 0.0 51.5 0.1 11.0 0.0 37.7 0.0 0.2 0.0 187.9 Lower Dee 1.4 0.0 758.0 0.0 12.5 0.0 0.7 0.0 2.5 0.0 0.0 Clwyd 0.5 0.1 14.3 0.0 0.3 0.0 82.0 0.0 0.6 0.0 19.4 Conwy 0.1 0.0 37.1 0.1 3.2 420.2 50.0 0.0 1.5 86.6 0.0 Gwrfai 0.0 0.0 32.7 0.4 0.4 9480.2 9.5 6.0 3.9 0.2 4.0 Dwytor 0.3 0.0 18.6 0.0 4.9 5.2 0.1 0.0 0.0 0.0 0.0 Glaslyn 0.0 0.0 5.4 0.0 0.1 6509.8 0.3 0.0 0.0 0.0 0.0 Artro, Mawddach 0.0 0.0 8.1 0.1 0.0 17.3 2.3 0.0 0.0 0.0 0.0 Dysynni 0.0 0.0 2.1 0.0 0.0 0.0 0.0 0.0 0,0 0.0 0.0 Dyfi, Leri 0.0 0.0 7.5 0.0 0.2 23.7 0.5 0.0 0.0 0.0 0.0 Rheidol 0.0 0.0 3.6 0.0 0.1 612.6 1.6 0.0 0.0 0.0 0.0 Aeron, Arth 0.0 0.0 0.0 0.0 1.0 0.6 1.0 0.0 3.5 0.4 0.0 Teifi 0.1 0.3 23.5 0.0 0.4 128.1 4.1 0.0 2.6 0.0 0.0 N. Pem bs 0.9 0.0 3.2 0.0 0.1 0.7 0.0 0.0 0.5 0.9 0.0 Cteddau 0.3 0.0 107.0 0.0 0.6 0.0 101.4 0.0 1.1 0.4 5.0 S. Pem bs 3.2 0.0 1.8 0.0 0.0 0.0 1.6 0.0 0.0 0.1 0.0 Taf 0.1 0.0 0.0 0.0 8.0 0.0 2.6 0.0 1.2 0.0 0.0 Gwendraeth 0.0 0.0 0.0 0.0 0.8 0.0 0.0 0.0 0.0 0.0 7.0 Upper Tywi 0.0 0.0 46.7 0.0 2.5 0.0 0.0 0.0 0.5 0.0 0.0 Cothi 0.0 0.0 0.2 0.0 0.1 0.0 0.0 0.0 0.0 0.0 0.0 Gwili 0.0 0.0 227.1 0.0 0.9 0.0 1.8 0.0 0.1 0.0 0.0 Gower 0.1 0.0 58.5 0.0 14.3 0.0 31.8 0.0 1.4 0.1 0.0 Loughor 0.0 0.0 6.8 0.0 1.1 0.0 0.0 0.0 0.0 0.0 0.0 Tawe 0.0 0.0 0.0 0.0 41.4 0.0 2.6 0.0 0.0 0.2 0.0 Neath 0.0 0.0 20.0 0.0 63.5 123.2 0.0 0.0 0.0 0.0 0.0 Afan, Kenfig 0.0 0.0 0.0 0.0 648.5 0.0 0.0 0.0 0.1 0.1 0.0 Ogmore 0.0 0.0 8.0 0.0 19.6 0.0 0.0 0.0 0.9 0.0 0.0 Thaw 0.1 0.0 0.0 0.0 7.5 0.0 0.0 0.0 0.0 0.0 1.4 Ely 0.0 0.0 0.4 0.0 20.3 0.0 0.0 0.0 0.0 0.0 0.0 Taff 0.0 0.0 277.7 0.0 25.1 0.0 18.2 0.0 2.1 0.0 0.0 Rhym ney 0.2 0.0 14.6 0.0 6.6 0.0 5.7 0.0 0.3 0.0 0.2 Ebbw 0.0 0.0 33.7 0.0 30.3 0.0 0.0 0.0 51.1 0.0 0.0 Upper Usfc. 0.1 0.0 158.7 0.0 0.9 0.0 2.1 0.0 0.0 0.0 50.0 Lower Usk 0.3 0.0 278.0 0.0 4.1 0.0 20.0 0.0 2.3 0.0 316.0 Upper Wye 0.0 0.0 376.2 0.0 0.1 0.0 7.3 0.0 1.0 0.0 0.0 Lower Wye 5.0 0.4 235.9 0.0 24.2 0.0 1.1 0.0 0.4 0.1 0.0 Lugg 2.2 0.1 2.6 0.0 2.0 0.0 14.1 0.0 0.1 0.0 0.0 Monnow 1.2 0.1 0.0 0.0 0.0 0.0 22.7 0.0 0.0 0.0 0.0 Use total 17 1 2909 1 957 17710 436 6 79 89 1837 Z „ v ~ , w Whole or part of subcatchment licence-exempt Categories of use 1 Spray Irrigation 2 Agriculture 3 Public water supply 4 Private water supply 5 Industrial 6 HEP 7 Fish farming 8 Electricity-cooling 9 Amenity/Conservation 10 Others 11 Transfe rs C:\JOBS\4432\SUMANALL.wk1 C2 1 4 -Ju n -9 4 APPENDIX D PWS SOURCES IN THE REGION WRWRS.REP/75F/27 June 1994 Table D.1 Dwr Cymru South East Div. supply area sources Dwr Cymru Licence Source Name Catchment Licensed < uantity Yield Comments S E Dtv supply area No* Average Peak (Ml/a) (Mid) (Mid) Southern CUA 55-17—019 Grosmont Spring (Greig Hilt) Monnow 28 0.06 0.06 55-17-250 Gar way Spring Monnow 28 0.08 0.06 55-17-258 Porthgalloed Borehole Monnow 35 0.10 0.00 DISUSED 55-17-400 Springs at LVnthony Monnow 6 0.05 0.0 DISUSED 55-18-408 R.Wye — Monmouth Intake LWye 48015 136.38 125.00 55-20-080 Newcastle Borehole Monnow 20 0.05 0.00 DISUSED 55-21-055 Mount on Brook and frlbutaries LWye 830 2.27 2.30 55-21-056 Rooerstone Grange borehole L.Wye 1344 3.41 3.40 55-21-057 Tlntwn Springs (Angidy Fechan Brook) LWye 83 0.27 0.00 DISUSED 55—21—050 Fedw Brook L.Wye too 0 36 0.16 55-21-067 Uandogo Spring L.Wye 41 0.11 0.11 55-21-100 Great Spring weU shaft L.Wye 3863 10.91 10.80 Nob 1 56-11-005 Parw-yr-Eos.Ynysyfro Reservoir LU sk 1659 4.55 1.50 56-11-007 P an t-yr-Eo s Reservoir and springs LU sk 1658 4.55 2.00 56-12-031 Springs atBlaenavon LU sk 60S 1.66 0.20 56—12—046 Various sources atCwmavon LU sk 682 2.27 1.00 56-12-047 Various points, Nantymaetor Reservoir L.Usk 909 2.97 0.60 56-12-040 Spring at Abersychan L.Usk 164 0.4S 0.00 DISUSED 56-12-050 Springs toCwmsyehan Reservoir L.Usk 455 1.36 0.00 DISUSED 56-12-051 Intake chambers to Perryrheol He sr. LU sk 1304 5.46 2.00 56-13-017 Uandegfedd Reservoir LU sk 68190 186.62 234.00 Note 2 5 6 - 21-029 Waun Springs LU sk 68 0.19 0.20 5 6 - 21-034 River Usk at Uantrlsiartt LU sk 28285 77.20 0.00 Note 3 56— 22—025 Polly Springs atGralg—y—Tar Wood LU sk 682 2.37 0.00 DISUSED 56—22—026 intake at Graig-y-Pandy Wood LU sk 582 1.59 0.00 DISUSED 56-31-050 Park Lodge — Uwyndu and C)bl Brook LU sk 1X3 2.70 2.00 56-31-054 Cate hpi tat Cherry Q chard LU sk 25 0.07 0.07 56-31-055 T yn -y—Warn Form L.Usk 283 0.77 0.50 5 6- 31-069 Deri Springs LU sk 2 0.01 0.00 OISUSED 56-32-016 Cw n MawrandCouUn Springs LU sk 374 1.02 0.00 DISUSED 56-33-003 Cairn Mound Reservoir U.Usk 546 2.55 0.00 OISUSED 56-33-004 Ffynnon Gisfaen Springs U.Usk 1400 4.00 2.40 5 6 - 34-012 Catch pi tat Uanbedr U.Usk 4 0.01 0.00 DISUSED 56-34-013 Catch pit near Cwm Gegyr Farm U.Usk 109 0.45 0.00 DISUSED 5 6 - 34-018 Grwyne Fawr Resr,,Grwyne Springs U.Usk 3505 9.61 6.90 56-35-007 Cwm Onneu Spring U.Usk 16 0.05 0.00 OISUSED 56-35-008 Ftynnon Itan Springs U.Usk 10 0.06 0.00 DISUSED 56-36-020 Springs atLlanbedr [5 on Map) U.Usk 163 0.77 0.00 DISUSED 56-36-021 Spring at Uanbec* (No. 8) U.Usk 10 0.03 0.00 DISUSED 56-36-023 Spring at Bwteh U.Usk 0 0.00 0.00 OISUSED 56 - 37-002 NantGbtefer Intake U.Usk 790 6.82 0.00 DISUSED 5 6 - 37-003 Two springs at Llangynidr U.Usk 1 0.07 0.00 DISUSEO 56-41-007 Talybont Reservoir U.Usk 26549 163.66 46.00 5 6 - 41-009 Spring at Uandetty U.Usk 1 0.00 0.00 DISUSED 5 6 - 62-010 Cwmcarn Colliery Ebbw 560 2.27 0.00 DISUSEO 5 6 - 62-011 Grai g - y - Cr o chan Ebbw 114 0.55 0.00 DISUSEO 5 6 - 62-012 NantCarn Ebbw 138 0.58 0.00 DISUSEO 5 6 - 63-011 C wm tiller y Reservoir Ebbw 1091 5.46 2.00 5 6 - 63-012 Coity Tunnel Ebbw 49 0.55 0.00 DISUSED - 56-64-000 Upper and Lower Carno Reservors Ebbw 3328 9.12 5.20 56-65-013 Conduit at Argoed Ebbw 1818 11.37 2.00 5 6 - 65-014 Shon Sheffrey Reservoir Ebbw 7001 30.00 5.20 56- 72-018 Wentwood Reservor LU sk 2489 6.82 4.00 57-11-001 Rhymney Bridge Reservoirs Rhymney 3148 6.62 3.60 57-12-033 Streams to Ljsvane Storage Reservoir Rhymney 2046 5.60 5.50 Note 1 57-12-034 Roath Park Lake Rhymney 136 0.37 0.00 DISUSED 57- 21-001 Tal Fawr Reservoirs Taff 34100 93.42 46.00 57 - 21-002 Tat Fechan Reservoirs Taff 38932 100.40 70.50 57 - 23-002 Bwllta and NantyMoel sources Taff 1185 12.20 2.00 57 - 23-005 Nantymoel Reseivor Taff 1010 2.86 0.00 OtSUSED 57 - 23-006 NaritCwmnanthir to Nanlhir Reservoir Taff 713 1.97 1.00 57 - 23-022 Ffrynantand stream to Pwltfa Reservoir Taff 436 1.20 0.00 DISUSED 57 - 23-046 River Dare to Bwllta Reservoir Taff 1825 4.99 0.00 DISUSED 57-23-049 River Dare to Bwllla Reservor Taff 666 1.82 0.00 OISUSED 57 - 23-050 River Dare to Bwllta Reserve* Taff 832 2.27 0.00 OISUSED 57 - 23 -060 Penderyn Boreho4e Taff 114 4.05 2.00 57 - 24-001 Uyn Fawr Resr. & Upper Rhondda Taff 7434 20.37 7.30 57-24-004 Nant Selsig Taff 1055 2.88 0.00 OISUSED 57 - 24-009 NantCwmparc and Nant Cetig Taff 1659 4.55 1.00 57-24-025 CasteII Nosand LluestWen Reservoirs Taff 5810 15.92 11.00 57-25-001 Clydachand Perthcelyn Reservoirs Taff 1793 4.91 2.00 5 7 - 25-002 NantClydach to Perthcelyn Reservoir Taff 68 0.19 0.00 DISUSED 57-25-015 Disused level atGwaelod- y-Garth Taff 91 0.25 0.00 DISUSED 5 7- 31-008 Collecting ppes to Pentyrch Reservor _ _E'y_ 138 0.37 0.00 DISUSED 56-11-002 Bigis wells Thaw 1818 5.00 5.00 Note 1 5 8 - 21-001 Borehole atLtansannor (Pwtlwy) Thaw 800 2.18 1.40 ZONE TOTAL 76 320836 1010.45 543.20 Noto4 c I'j obs\4432\yields. wk3 2 4 - Jur»-94 Table D.1 Dwr Cymru South East Div. supply area sources Dwr Cym ru Licence Source Name Catchment Licensed c uantlty Yield Comments SE Div supply area No* Average Peak (Ml/a) (Mid) (Mid) Monmouth 5 5 - 20-087 Redwern Springs Monnow 22 0.06 0.00 DISUSED 5 5 - 21-066 Ffyrtnon Gaer Springs L.Wy* 163 0.30 0.50 55—18-201 R.WyeatMonmouth (May Hill) L.Wye 1244 3.41 3.40 5 5 -1 8 -2 0 3 Buck holt Spring* L.Wye 714 1.95 0.40 z o n e Y o t a l 4.00 2182 5.92 4.30 Hereford CUA 55— 09—102 Dllwyn Borehole Lugg 32 0.09 0.09 5 5 - 09-204 River Arrow — Hardest Lugg 396 1.09 0.00 DISUSED 5 5 -0 9 -3 3 0 Dunfold boreholes Lugg 1206 3.30 3.30 55-12-431 Well at M .Summer Meadow, Leominster Lugg . 1195 3.27 3.30 5 5 -1 2 -4 3 2 Wlthington Boreholes Lugg _ 2G5 0.73 0.00 DISUSEO 55-13-061 Bredenbury Borehole Lugg 16 0.04 0.00 DISUSED 5 5 -1 5 -2 4 6 R.Wyeat Broomy Hill LWye 16367 44.72 44.70 5 5 -1 7 -3 0 5 Malt House Spring Monnow 2 0.01 0.00 DISUSED 55—19—079 Keety Spring (St.Weonards) L.Wye 90 0.30 0.30 55 -1 9 -0 8 1 Uancloudy Spring L.Wye 7 0.02 0.00 DISUSED ZONE TOTAL 10.00 16580 53.57 52.69 Note 5 Whitbourne 5 4 - 0 9 - 000 32B5 9.00 8.80 Note 6 ZONE TOTAL : 3295 9.00 0.00 Lelntwardlne 54—09— 367 3GG 1.00 1.00 Note6 ZONE TOTAL . 365 1.00 1.00 Alton Court 5 5 -1 8 -2 0 8 Alton Court Borehole L.Wye 830 227 2.30 5 5 -1 8 -2 2 0 Coughton boreholes LWye 13U 3.60 3.60 DISUSED ZONE TOTAL : .2144 .5.87 11.30 Note 7 Vowchurch & 5 5 -1 5 -2 4 7 R^er Wye (Eaton Bishop) LWye 996 2.73 2.70 Dor stone 55-17-451 Vowchurch boreholes Monnow 1464 4.00 3.00 55 -1 7 -2 5 1 Dorstone Spring Monnow 75 0.40 0.10 5 5 - 20-096 Skenfrith Borehole Monnow 5 0.01 0.00 DISUSEO ZONE TOTAL - .. . 1544 4.41 3.10 Ports & 5 6 - 44-016 Boreholes at Brecon U.Usk 1281 3.50 5.80 Brecon bhs 5 6 - 45-008 Cwrt Gilbert Farm U.Usk 740 2.05 0.00 OISUSED 5 6 - 54-002 Rh/er Trinant U.Usk 262 0.77 0.00 DISUSED ZONE TOTAL 2308 6.32 5.80 Uyswen & 5 5 - 06-078 R.Wyeand Uan-Bwich-Uyn Lake U.Wye 1S27 4.18 3.60 Uandello Qraban 55 -0 6 -1 0 0 Bach Howey Brook U.Wye 1096 3.00 0.40 ZONE TOTAL ■ 2625 , . 7.18 4.00 Pilletfi & Farwell/ 5 5 - 08-046 Harley Valley stream Lugg 141 0.39 0.30 Harley Valley 5 5 -0 8 -1 2 5 Rfcrer Lugg (Byton) Lugg 415 1.14 1.00 Note 8 5 5 -0 8 -1 7 9 Four boreholes Lugg 1409 3.86 3.80 ZONE TOTAL , '1985 ,5 .3 9 4.10 Elan CUA 5 5 -0 1 -0 0 7 Elan Reservoirs U.Wye 133107 388.00 34100 Note 8 5 5 - 02-078 Cwm Owfnant Brook U.Wye 332 0.91 0.00 DISUSED 55— 03—038 R.Wyeat Builth U.Wye 1348 3.68 3.70 5 5 - 04-002 Well at Uanbister U.Wye 9 0.03 0.00 DISUSED 5 5 - 04-026 Uanbadarn Fynydd Springs U.Wye 6 0.03 0.00 DISUSED 5 5 - 04-028 Uanfihangel Rhydithon Spring U.Wye 91 0.25 0.10 5 5 - 04-029 Llaithddu Spring U.Wye 1 0.00 0.00 DISUSED 5 5 - 04-069 Three Wells Spring U.Wye 512 0.91 0.00 DISUSED ZONE TOTAL 135405 39141 8.80 SU PPLY A R EA TO TA L 4B8569 1491 647 Notes: 1 Non-poteble supply licence (excluded from zone yield) 2 Including 77.3MI/d reserved for non—potable supply (excluded from zone yield) 3 Yield included in Uandegfedd licence yield 4 Including 22.3MI/d fransfer from Felindre/Schwyll supply zone 5 Including 1 Ml/d transfer from Pilleth & Fair well supply zone 6 Import from Severn-Trent Region 7 Including 9MI/d sold to DC by Severn — Trent Water Pic 8 Transfer to Hereford CUA 9 Export by Severn-Trent Water Pic (5Ml/d sold to DC) c : V o b s \4 4 3 2 \y i el d s . wk3 D2 24 —Jun —64 Table D.2 Dwr Cymru South West Div. supply area sources Dwr Cymru Licence Source Name Catchment Licensed < uaniity Yield Comments S.W.Div supply area Nos Average Peak (Ml/a) . (Mid) (Mid) ; Pem broke*hire CUA 61-01-001 Pont Brynbernn N.Pembs 205 0.77 0.60 61-01-002 Pomtaen (Pontygotti) N.Pembs 500 1.45 0.00 OISUSED 61-02 -031 Rwet Sd vaat Middle Mil) N.Pembs 100 1.36 1.30 61-03-001 W.Cledctau at Crow hill Cleddau 7728 27.28 10.00 61-03-002 Hotwellsaftd Glanrhyd Cleddau 455 1.73 1.00 61-04 -001 Prescelly No.l. Reservoir Cteddau 5910 18.23 7.40 61-04-010 Ltysyfran Res. - Cana* ton Bridge Intake Cleddau 23000 85.00 57.70 Note 1 61-00 -001 Stem bridge steam S.Pembs ' 650 2.55 0.00 DISUSEO ZONE TOTAL 40548 138.37 45.50 Note 2 North Ceredglon 63-01-005 Uyn Llygad Rheidol, M aesnantiteam Rheidol 929 2.55 2.30 63-01-027 Mae* nant and NantyMoch streams Rheidol 372 8.18 0.50 63-01-029 Parcel Ganot borehole — Love* grove Rheidol 1300 5.00 5.00 64-12-001 Uyn C raig -y - Plstyll Dyfl 106* 9.10 3.00 ZONE TOTAL 4465 24.83 10.60 Middle & 60-02-002 Ffynnon Nanto Cothi 63 0.23 0.23 South Ceredigion 62-01-057 Teifi Pools Teifi 2023 7.73 8.70 62-01—058 Pencefn Teifi 59 0.22 0.00 DISUSEO 62- 01-060 Otwen Borehole Teifi 144 0.40 0.40 62- 03-005 Teifi at Ueehryd Teifi 5750 18.00 19.00 ZONE TOTAL B776 27.36 26.10 Fellndre/Schwyti 56-53-002 Cray Reservoir U.Usk 15775 43.19 20.40 56-54-001 Usk Reservoir U.Usk 13274 42.73 5.00 58-41-002 River Uynfi at Btaencaerau Ogmore 682 1.86 1.90 58-42-012 Hendre Itan Goch Springs.Gilbch Goch Ogmore 04 0.17 0.00 DISUSED 58-42-001 Ogwr Fawr and un—named stream Ogmore 9S5 2.81 2.60 58— 42—002 Nant y M oei to Hi^i Level Reservoir Ogmore 818 2.24 2.20 58— 42—009 Nant Ffesg, Nant lechyd and tlbutary Ogmore 477 1.30 1.30 5 8 - 44-005 Borehole and well, Bridgend Ind. Estate Ogmore 1102 . 4.21 3.20 58-44-012 Borehole at Bridgend Ind. Estate Ogmore 996 2.73 2.70 58- 44-06 Schwyil Pumping Station Ogmore 7 056 21.80 21.60 Noto 3 59- 02-050 Headwaters of Loughor Loughor 2489 6.82 6.80 59-03-022 Cwm Uiedi ^servoir Gower 69*7 19.03 4.40 Note* 59-03-023 Upper Uiedl Reservoir Gower 6703 18.37 6.50 59-04-048 Springs at Hoiywdl, Pitton and Parkmlll Gower 400 3 20 2.40 59- 04-065 Lliw Reservoirs Gower 7728 21.17 10.30 60- 01-001 Uynyfan Reservofr U.Tywl 3783 10.36 4.00 GO-01-068 Tywi - Manorafon abstraction L.Tywi 13274 36.37 36.40 6 0 - 03-035 Tywi at Nantgaredig Gwili 62966 227.30 2Z7.30 Noto 5 ZONE TOTAL .166468 ,465.47 332.50 Tonn 6 0 - 01-065 Tonn Borehole U.Tywi 244 0.70 0.70 ZONE TOTAL : • .,24* 0.70 .0.70 Ystmdfellto 58-71-001 Ystradtdite Reservoir Neath 7300 20.00 15.20 ZONE TOTAL-;. ■ 7300 20.00 15.20 SUPPLY AREA TOTAL 227803 677 431 Notes: 1 Including 37.3MI/d reserved for non-pobble supply (excluded from zor.t 2 Including 4.B Ml/d In liesr.co-exempt area (Park Springs end Milton) 3 Sou res due to be mothballed by 1996 4 Non-potable supply licence (excluded from zone yield) 5 Including 22.3 Ml/d transfer to Southern CUA (excluded from zone yield) c;^obsVU32\yields.wk3 D 3 2 4 - Ju n —94 Table D.3 Dwr Cymru Northern Div.(W) supply area sources Dwr Cym ru Licence Source Name Catchment Licensed a uantity Yield Comments NE Div supply area Nos Average Peak (Ml/a) (Mid) (Mid) North Eryrl/Yn^ Mon 6 5 -0 4 -0 0 6 Mon Cwmllan at Nant Gwynant Glaslyn 5 0.01 0.00 DISUSED 6 5 -1 4 -0 0 2 Jyn Cwm Dulyn Gwrfai 833 3.30 3.20 65-14-021 Spring at Geuian, Nan tile Gwrfai 60 0.28 0 00 DISUSED 65—15—01B Afon Gwyfral at Llyn Cwellyn/Nart Mill Gwrfai 5624 15.86 12.00 65 -1 5 -0 2 2 Afon Gwyfrai at BontNewydd Gwrfai 1 0.05 0.00 DISUSED 65 -1 6 -0 0 9 Aton Rhythallt, Uanrug, Caafnarfon Gwrfai 1245 3.41 3.40 6 5 -1 6 -0 6 4 Jyn Marchlyn Bach Gwrfai 1460 4.00 0.00 DISUSED 6 5 -1 0 -0 0 8 A.Uafar/Celnllusg/Gwsrn Saeson Bach Gwrfai 2900 7.09 1.10 6 5 -1 8 -0 1 5 Afon C ase s, Bethescta Gwrfai 409 1.14 1.14 66— 08—010 Ffynnon Llugwy, Capel Curig Conwy 2828 7.73 9.00 102—CC—007 Cefnl Reservoir Angbsey 5475 15.X 10.00 ICE—06—006 A law Reservoir, R h o s-y-B o l Anglesey 8837 34.10 25.50 ZONE TOTAL 2S271 92.05 65.34 Nant Peris 6 5 -1 6 -0 6 3 Plstyll Dwr Oer spring and Nant Peris Gwrfai 44 0.12 0.10 ZONE TOTAL 44 0.12 0.10 Cwm ysfrad llyn/ 6 5 - 08-016 Afon Dwyfcr, Garndolbenmaen Owyfor 2310 8.40 0.00 DISUSEO Dolbenmaen 6 5 - 08 -019 Uvn Cwmyst-adllyn Owyfor 4491 12.30 12.50 ZONE TOTAL 8801 20.70 12.50 Uyn Cynwch 64-03-000 Spring at Glascoed Farm, Uanfachraeth Mawddach 9 0.02 0.00 0 IS U S E0 64— 03—023 Afon Gamlan, Ganllwyd Mawddach 13 0.04 0.00 DISUSED 8 4 - 04-064 Spring at Gotwyr & frlbutary of Wnlon Mawddach 25 0.24 0.00 DISUSED 8 4 -0 4 -0 6 5 Uyn Cynwch Mawddach 600 2.00 2.00 6 4 -0 4 -0 6 0 Spring at Penrhlw farm, Dolgellau Mawddach 30 0.08 0.08 OISUSED ZONE “TOTAL . :677 2.38 2.08 Barmouth Junction 6 4 - 05-037 BronLletTyltan.Cyfannedd Uchaf Mawddach 175 0.61 0.61 ZONE TOTAL : 175 : 0.61 0.61 Bontddu 64-05-024 Aton Cwm Mynach, Maesfryfer Mawddach 4 0.01 0.00 DISUSEO 6 4 - 05-026 Aton Cwm L be hen Mawddach 33 0.14 0.10 ZONE TOTAL „ -37 0.15 0.10 Penybont 64-13-031 Afon Fa the w Dycynnl 680 2.60 2.60 0 4 -1 3 -0 0 5 Spring near Crychnortt, Aberdyfi Dysynnl 10 0.04 0.00 OISUSED ZONE TOTAL ■■.695 2.64 2.60 Garregllwyd 64-01-001 Uyn GelllGaln, Bronaber Mawddach 341 1.38 0.50 6 5 - 01-002 Uyn Morynion Glaslyn 996 3.27 2.40 65 -0 1 -0 1 6 Spr. at Talywaenydd.Uechwedd Quarry Giaslyn 3 0.01 0.00 DISUSED 6 5 - 02-006 Springs: Ffridd Odu and Moel Oernant Glaslyn 207 0.91 0.00 DISUSEO ZONE TOTAL . .. 1546 5.55 2.90 Gllf or 6 5 - 03-001 Tallin Stream and tTyn Yecwyn Uchaf Glaslyn B30 3.41 2.80 6 5 -0 6 -0 2 0 Un—named stream at Ogof Uechwyn Glaslyn 5 0.01 0.01 OISUSED 65- 06-021 Afon Maesq wm, Croesor Glaslyn IQS 0.29 0.29 ZONE TOTAL , . . ' 940 .3.71 .3.10 Rhiwgoch 84 -1 6 -0 0 8 Uyn Elddew Mnwr Reservoir Mawwdach 630 2.27 1.50 65 -0 3 -0 0 9 Aton Eianqruq Glaslyn 33 0.09 0.00 DISUSED ZONE TOTAL - 863 2.36 .1.50 Uyn Bodl yn 84 -1 5 -0 0 9 Uyn Bodlvn, Dytfryn Ardudwy Mawwdach 980 3.00 2.20 6 4 -1 6 -0 0 2 Sprtng:Caerffynnon Farm.Dyffryn Ardudwy Mawwdach 106 0.46 0.00 OISUSED ZONE TOTAL . 1088 3.48 2.20 YG aer 8 4 -1 3 -0 0 6 Spring: Llanerch Goediog, nr. Aberfrinant Dysynni 1 0.00 0.00 DISUSED 64—13—008 Cwm Uchaf, Lhneqryn, Tywyn Dysynni 100 0.27 0.00 DISUSED 64-13-011 Ffynnon Badriq, Llaneqryn, Tywyn Dysynni 23 0.06 0.00 DISUSEO 6 4 -1 4 -0 0 2 Catettwr.Piqyra11t,Parthyqwyddweh Spr. Mawwdach 91 0.44 0.40 6 4 - 14-003 Afon Gwril, Bodwylan, Uwyngwril Mawwdach 150 0.65 0.65 ZONE TOTAL 373 1.43 1.05 Dinas Mawddwy 64 - 06-005 Aton Cywarch, Abereywarch □yfi 2 0.01 0.00 OISUSED 6 4 - 06-010 Pen y Graig, Cwm Celydd Oyfi 2 0.01 0.00 DISUSED 6 4 - 06 -017 Springs at Brynllys, and Nant Mirillyn Oyfi 110 0.30 0.11 64 - 06-01B Surface spring near Bryn, Lfa nymawddwy Oyfi 22 0.06 0.06 ZONE TOTAL 135 0.38 0.17 C orris/Pen naJ 64-10-001 Hafoty Reservoir, Corns Oyfi 148 0.41 0.07 6 4 -1 1 -0 1 5 NantCwm yGof, Cwrt, Pennal Dyfi 120 0.70 0.30 DISUSED ZONE TOTAL 269 1.11 0.37 Abergynolwyn 6 4 -1 3 -0 3 0 Spring at Talyllyn RS — Aberqynolwyn Oysynni 40 0.20 0.20 ZONE TOTAL 40 0.20 0.20 Betws y Coed 66 - 06-004 Uyn Elsi, nr. Betws y Coed Conwy 150 1.09 1.09 ZONE TOTAL 150 1.09 1.09 Dotwydddan 66 - 06 -007 Ceunant y Garnedd, Mountain Reservoir Conwy 68 0.65 0.34 ZONE TOTAL 68 0.65 0.34 Capel Curig 6 6 - 08-002 Afon y BedOl.Captl Curig Conwy 68 0.32 0.30 ZONE TOTAL 66 0.32 0-30 SU PPLY A R EA TO TA L 43240 139 97 c ob sV*432\y elds.wk3 0 4 2 4 - J u n - 9 4 Table D.4 Dwr Cymru Northern Div.(E) supply area sources Dwr Cyrmu Ucenca Source Name Catchment Licensed c uantity Yield Comments NW Div supply area Nos Average Peak (Ml/a) (Mid) (Midi Llanfalrtechan 65-19-004 Uyn Anafon Gwrfai 63) 2.73 1.10 65-10-005 Afon DduatLtenfairfechan Gwrfai 16 0.55 0.00 DISUSED 65-10-007 Afon Q hn Sais Gwrfai 166 0.55 0.24 65-10-009 Afon Anafon Gwrfai 4 0.14 0.14 ZONtTrOTAL 1016 3.97 1.48 Atwen/Bretton CUA 67-04-016 Alwen Reservoir U.Dee 1093 45.46 35 50 67 -08-048 Stream atMoel Fammau.CUcain L.Dee 60 0.19 0.10 67 -08-056 4 Reservoirs and pond atCllcein. Mold L.Dee • 1364 5 00 1.50 67 -08-079 Brithdtr Mawr Intake L.Dee 771 4,55 0.00 DISUSED 67-09-148 Dee - Poulton, Chester LDee 602 23.64 23.60 67-10-083 tndustial Main, rt»lkyr> L.Dee 468 1.36 0.00 DISUSEO 67-10-087 Boreholes in Kinnertonarea, Chester LDee 277 6.55 0.00 DISUSEO 67-10-113 Nant y Fflint LDee 4S6 1.36 0.00 DISUSED ZONtTfOTAl 26662 86.11 60.70 Cowiyd/Dulyn 66-10-001 Uyn Cowlydllyn Dutyn and Melynllyn Conwy 9002 36.37 34.20 65-19-011 Afon Oyrach Impounding Reservoir Gwrfai 4 0.01 0.01 DISUSED ZONETOTAL 9006 36.38 34.21 Uyn Conwy 66-01-001 Uvn Conwy Conwy 1245 3.41 3.67 66 -01-004 Uyn Conwy Conwy 132 1.42 0.00 01SUSED 66 -04-009 Afon Gtescwm, Penmachno Conwy 90 0.33 0.00 DISUSED ZONE TOTAL 1475 9.10 3.67 Uyn Atenlg Fawr 87 -02-006 LWn Arenig Fawr c b 3 630 2.27 2.30 67-03-009 Spring at Bryn Melyn Fa/m, Uandderfei U.Dee 17 0.05 0.00 DISUSEO ZONE TOTAL 646 2.32 2.30 Glascoed/ 66-01-038 Plas yr Esgob Clwyd 1178 9.83 3423 Trecastell 66-01-041 EtaII Newydd Borehole Clwyd 318 1.32 0.67 66-02-001 Clywedog Reservoir Clwyd 232 0.82 0.00 OISUSED 66-03-028 Uwyn Isaf Boreholes Clwyd 996 3.27 2.70 86-03-048 Uannerch Paik Boreholes Clwyd 3410 13.64 13.60 66-06-007 Plas Uchafand Doiwen Reservort Clwyd 5000 18,18 11.40 66-07-003 Mlneshaftat Mid-Nant Farm, Prestatyn Clwyd 162 1.62 1.62 66-07-034 Ftynnon Asaph Clwyd 1637 4.55 1.90 ZONETOTAL.. 12952 53.43 35.S2 SU PPLY AREA TO TAL 54047 189 138 Table D.5 Wrexham & East Denbighshire Water Co. sources WEDWC Licence Source Name Catchment Licensed < uantity Yield Comments Company area Nos Average Peak (Ml/a) (Mid) (Mid) 67-05-02 Trefnant Brook M.0ee 406.07 1.55 0.15 DISUSED 6 7 -0 5 - 03 Penycae Ftoservors M.Dee 906.66 3.41 2.18 67-05-04 Oerog springs M.Dee 1160.70 3.41 2.50 67-05-06 Rfcer Dee — Berwyn M.Oee 678.90 2.27 0.00 67-05-07 Vived M.Dee 33106 1.36 0.00 Nate 1 6 7-05- 06 Nant y Crogfrin M.Dee 0.00 0.00 0.00 Transfer 6 7-05- 24 New ha 11 Springs M.Dee 32S.31 2.05 0.15 Note 1 67-06-17 Glynceiriog Springs M.Dee 103.45 0.64 0.00 Note 1 6 7-06- 33 Tregeiriog M.Dee 36.50 0.10 0.06 Note 1 87-07-05 River Dee - Bangor-is-y-coed M.Oee Noto 2 67-07-35 Park Day levet/Speedwell shaft M.Dee 2216 9.62 2.50 Noto 1 67-07 - 36 Ty Mawr & Cae Llywd reservoirs M.Dee 2448 11.37 3.41 67-07-37 Talwm Borehole M.Dee 271 S3 1.43 1.00 Note 1 67-07-182 River Dee - Banqo r-is-y—coed M.Dee 13805 40.81 43.41 6 7-06- 03 Nantyffrith Reservor L.Dee 359.89 1.23 0.80 Note 1 67-06-10 Pendinas reservoir and springs L.Dee 1469 5.46 2.27 COMPANY TOTAL* 24613 85 53.8 Note 3 Nptes: 1 To bo dosed in near future 2 Included with 67-07-182 3 Yield after closures Table D.6 Chester Waterworks Co. supply area sources CWC Licence Source Name Catchment Licenced quantity Yield Comments Company area Nos Average Peak (Ml/a) (Mid) (Mid) 67 -0 9 - 03 Dee — Ebrrelwell Hill, Chester L.Dee 12456 34.10 32.60 68-06-11 Piemstetl borehole 840 2.30 1.80 Note 1 COMPANY TOTAL 13295.5 36.4 34.6 Notes: 1 Import from NW Region c:'jobsV4432\yioids.wk3 05 24—Ju n -8 4 APPENDIX E COMPARISON OF LICENSED QUANTITIES AND ACTUAL ABSTRACTIONS WRWRS.REP/75F/27 June 1994 I I % E COMPARISON OF ACTUAL ABSTRACTIONS AND LICENSED QUANTITIES E.l GENERAL In order to assess the net demand on water resources a comparison of licensed quantities and actual abstractions and yields has been carried out. This analysis was extended to include 1981, 1986, and 1991, as well as 1992, in order to improve the reliability of assessments of estimated abstractions and provide forecasts of historic demands based on the returns data. E.2 DATA ANALYSIS For each category of use and water source the abstracted quantity was compared with the licensed quantity to determine the % taken. In order to assess the reliability of the calculated figures the licensed quantity of returns was compared with total licensed quantity. The results of the analysis are presented in Tables D1 to D4. During the analysis it was found that, as well as there being substantial gaps in the records, there were a significant number of erroneous figures for actual abstractions which were rectified(eg returns as much as 1000 x licensed annual quantity). In analysis of returns for HEP licences it was found that three large schemes - Dinorwic, Ffestiniog and Trawsfynydd - which account for about 85% of the licensed quantity, had returns data for only a few years. As these licences have no significant impact on resources they were excluded from the analysis. The following observations are made on the results of the analysis:- (i) The available returns data is not complete - on average only around 50% of total licensed quantity is accounted for. Annual returns are missing for licences of all sizes; (ii) In general total abstraction is generally between 30% and 50%; (iii) The % total licensed quantity accounted for in Public Water Supply, Industrial and Electricity-cooling is generally above 70%. In other uses typically less than 50% of licensed quantity is accounted for; (iv) The actual abstractions in several categories of use are above 100% ofthe licensed quantity in odd years, but these occur in very small sample sets; E.3 ACTUAL ABSTRACTION FACTORS To estimate the actual abstractions made the percentage of licensed quantity taken, derived from the analysis described above, was used as the basis for setting Actual Abstraction Factors (AAFs) - multipliers to be applied to the total licensed quantity to estimate actual abstraction or gross demand. It is assumed that in general terms the % taken is indicative of water demand, though clearly the data from which these figures have been derived is not very reliable in many cases. WRWRS.REP/75F/27 June 1994 Page El The Welsh Region of the NRA undertook a similar comparison exercise in 1990 based on 1989/90 returns. The results of analysis undertaken in this study were compared with the NRA analysis and were found to be generally in agreement. In setting the AAFs the following factors have been taken into account:- (i) General In certain categories of use the proportion of the total licensed quantity accounted for is low and the reliability of the % taken as an indicator of overall demand is therefore poor. In these cases AAFs have been set conservatively or based on results of the NRA’s analysis if more reliable; (ii) Spray irrigation Spray irrigators, unlike other licensees, can pay a lower abstraction charge if they abstract less than their annual entitlement. Abstractors are therefore more likely to make a return if they have taken less than their annual entitlement. This introduces bias in the analysis which is likely to result in underestimation of total abstraction. The AAFs for spray irrigation have therefore nominally been set at 10% above calculated % taken figures; (iii) Hydroelectricity It is assumed that the % taken is indicative of abstractions for the three pumped storage schemes excluded from analysis. The returns data for these licences indicates that this is conservative with abstractions in the range 20% to 50%. (iv) In a few instances % taken exceeds 100% of licensed quantity. Whilst the figure may well be correct in individual licences clearly this is not indicative of overall demand in a particular category of use. In these instances the AAF has been set in line with figures for other years. The AAFs, set in accordance with the above criteria, are presented in Table E.5. Page E2 WRWRS. REP/75F/27 June 1994 Table E.l Comparison o f licensed quantities and actual abstractions for 1981 Returns data Category of use Total Licensed % Total Abstracted % taken licensed quantity licensed quantity quantity quantity (Ml/a) (Ml/a) (Ml/a) Surface water - Agriculture 55 - - - - - Amenity/Conservation 1248 382 31 382 100 - Electricity - cooling 1820603 1820608 100 431431 24 - Fish farming . 37464 5923 16 7765 131 - Hydroelectricity 691874 541223 78 497744 92 - Industrial 531595 511847 96 346028 68 - Public Water Supply 1055616 837976 79 571835 68 - Private water supply 70 1 2 < 1 26 - Spray Irrigation 3762 1656 44 262 16 - Other 128 53 42 3 5 Groundwater - Agriculture 4975 20 1 28 137 - Amenity/Conservation 2 - - - - - Electricity - cooling 0 - - -- - Fish farming 249 - - - - - Hydroelectricity 0 - -- - - Industrial 22246 18084 81 11373 63 - Public Water Supply 56754 48317 85 31278 65 - Private water supply 443 165 37 108 66 - Spray Irrigation 408 131 32 5 4 - Other 178 82 97 54 66 WRWRS.REP/75F/27 June 1994 Page E3 Table E. 2 Comparison o f licensed quantities and actual abstractions for 1986 Returns data Category of use Total Licensed % Total Abstracted % taken licensed quantity licensed quantity quantity quantity (Ml/a) (Ml/a) (Ml/a) Surface water - Agriculture 77 23 30 0 0 - Amenity/Conservation 2462 2462 100 750 28 - Electricity - cooling 1820608 1820608 100 249941 14 - Fish farming 39537 20591 52 14407 70 - Hydroelectricity 702140 541488 77 214967 40 - Industrial 538201 517628 96 309065 60 - Public Water Supply 1055616 861967 82 573350 66 - Private water supply 75 1 2 1 97 - Spray Irrigation 4891 3827 78 748 19 - Other 261 56 21 3 5 Groundwater - Agriculture 5034 103 2 26 25 - Amenity/Conservation 17 - - - - - Electricity - cooling 0 - - - - - Fish farming 322 - - - - - Hydroelectricity 0 - - - - - Industrial 24551 19453 79 9477 56 - Public Water Supply 66333 56334 85 32957 58 - Private water supply 508 55 11 31 56 - Spray Irrigation 715 543 76 178 33 - Other 179 28 16 12 41 Page E4 WRWRS.REP/75F/27 June 1994 Table E.3 Comparison of licensed quantities and actual abstractions for 1991 Returns data Category of use Total Licensed % Total Abstracted % taken licensed quantity licensed quantity quantity quantity (Ml/a) (Ml/a) (Ml/a) Surface water - Agriculture 387 168 43 15 9 - Amenity/Conservation 26183 3190 12 1460 46 - Electricity - cooling 1820608 1818400 100 182093 10 - Fish farming 157286 39373 25 30543 78 - Hydroelectricity 860774 430733 50 295259 69 - Industrial 539909 519462 96 168114 32 - Public Water Supply 1062359 771961 73 462793 60 - Private water supply 207 1 < 1 1 81 - Spray Irrigation 6197 4176 67 721 17 - Other 32490 603 2 125 21 Groundwater - Agriculture 5524 247 4 32 13 - Amenity/Conservation 37 - - -- - Electricity - cooling 0 --- - - Fish farming 714 73 10 55 75 - Hydroelectricity -- -- . - Industrial 26116 17893 69 8857 50 - Public Water Supply 74582 57871 78 - 33067 57 - Private water supply 596 154 26 58 38 - Spray Irrigation 914 575 63 189 33 - Other 188 1 <1 < 1 67 WRWRS.REP/75F/27 June 1994 Page E5 Table E.4 Comparison o f licensed quantities and actual abstractions for 1992 Returns data Category of use Total Licensed % Total Abstracted % taken licensed quantity licensed quantity quantity quantity (Ml/a) (Ml/a) (Ml/a) Surface water - Agriculture 387 154 40 21 14 - Amenity/Conservation 28519 5358 19 • 1955 36 - Electricity - cooling 1820608 1818400 100 270640 15 - Fish farming 163178 50257 31 26158 52 - Hydroelectricity 896138 632365 71 425390 67 - Industrial 540448 521003 96 148038 28 - Public Water Supply 1062392 946517 90 649599 69 - Private water supply 224 13 6 1 10 - Spray Irrigation 6373 4564 72 1183 26 - Other 32492 32226 99 143 0 Groundwater - Agriculture 5554 272 5 68 25 - Amenity/Conservation 39 - - - - - Electricity - cooling 0 --- - - Fish farming 714 73 10 0 0 - Hydroelectricity ------Industrial 26131 18848 72 12981 69 - Public Water Supply 74582 57341 77 33971 59 - Private water supply 611 182 30 85 46 - Spray Irrigation 968 714 74 689 96 - Other 190 1 < 1 <1 53 Page E6 WRWRS. REP/75F/27 June 1994 Table E.5 Actual Abstraction Factors Source Purpose Actual Abstraction Factor 1981 1986 1991 1992 Surface Water Agriculture 65 65 65 65 Amenity/Conservation 35 28 40 40 Electricity - cooling 24 14 10 15 Fish farming 50 50 50 50 Hydroelectricity 50 40 69 67 Industrial 68 60 32 28 Public Water Supply 68 67 60 69 Private water supply 60 60 60 60 Spray Irrigation 26 20 27 36 Other 5 5 1 1 Groundwater Agriculture 80 80 80 80 Amenity/Conservation 40 40 40 40 Electricity - cooling --- - Fish farming 50 50 50 50 Hydroelectricity - - - - Industrial 63 49 49 69 Public Water Supply 65 59 57 59 Private water supply 60 60 60 60 Spray Irrigation 30 43 43 96 Other 50 50 50 50 WRWRS. REP/75F/27 June 1994 Page E7 APPENDIX F ESTIMATED GROSS ABSTRACTIONS IN SUB-CATCHMENTS WRWRS.REP/75F/27 June 1994 I Table F.1 Estimated abstraction in 1993 from groundwater in the Region (Gross daily average Ml/d) Subcatchment U se 1 2 3 4 5 6 7 8 9 10 ?Arisl6sey>" ■ - 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 'JiJlX&rDeQ'' T- 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Middle Ge^., 0.2 1.1 6.8 0.1 2.5 0.0 0.3 0.0 0.0 0.0 louver pee '■ •• ' 0.2 1.0 19.1 0.2 10.3 0.0 0.0 0.0 0.0 0.1 0.0 0.2 10.7 0.0 0.8 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.2 0.0 0.3 0.0 0.0 0.0 0.0 0.0 iV; 0.0 0.0 0.0 0.0 0.1 0.0 0.0 0.0 0.0 0.0 ^ ; 0.0 0.0 0.3 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.7 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 CJyftiLerl". - 0.0 0.0 0.2 0.0 0.0 0.0 0.0 0.0 0.0 0.0 iRheWolv-'-v .V- 0.0 0.0 2.1 0.0 0,0 0.0 0.0 0.0 0.0 0.0 Asrom, Aith , ' . , 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0,0 0.0 JbM:, , s.v, / 0.0 0.2 0.3 0.0 0.0 0.0 0.0 0.0 0.0 0.0 *N,:Peinbs".- ■”>/: ' 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 'Cfeddau- ' 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 :Si.Pem bs 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 m - •••'•• • 0.0 0.4 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.2 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 [ipeerlSS.!! .... 0.0 0.2 0.4 0.0 0.0 0.0 0.0 0.0 0.0 0.0 ?■■:v ;Q Whole or part of sub-catchm ent licence-exem pt Categories of use 1 Spray Irrigation 2 Agriculture 3 Public water supply 4 Private water supply 5 Industrial 6 HEP 7 Fish farming 8 Electricity-cooling 9 Amenity/Conservation 10 Others C:\JOBS\4432\SUMANALL.wk 1 F1 1 4 -Ju n —94 Table F.2 Estimated abstraction in 1993 from surface water in the Region — excluding tidal abstractions (Gross daily average Mi/d) Subcatchment Use 1 2 3 4 5 6 7 8 9 10 Anglesey 0.0 0.0 26.7 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Upper Dee 0.0 0.0 34.7 0.0 0.1 260.2 6.8 0.0 0.2 0.0 Middle Dee 0.4 0.0 35.5 0.0 3.1 0.0 18.8 0.0 0.1 0.0 Lower Dee 0.5 0.0 523.0 0.0 3.5 0.0 0.3 0.0 1.0 0.0 Clwyd 0.2 0.0 9.9 0.0 0.1 0.0 41.0 0.0 0.2 0.0 Conwy 0.0 0.0 25.6 0.0 0.9 281.5 25.0 0.0 0.6 0.9 Gwrfai 0.0 0.0 22.5 0.2 0.1 6351.7 4.8 0.9 1.5 0.0 Dwyfor 0.1 0.0 12.8 0.0 1.4 3.5 0.1 0.0 0.0 0.0 Glaslyn 0.0 0.0 3.7 0.0 0.04361.5 0.2 0.0 0.0 0.0 Artro, Mawddach 0.0 0.0 5.6 0.0 0.0 11.6 1.1 0.0 0.0 0.0 Dysynni 0.0 0.0 1.5 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Dyfi. Leri 0.0 0.0 5.2 0.0 0.0 15.8 0.3 0.0 0.0 0.0 Rheidol 0.0 0.0 2.5 0.0 0.0 410.5 0.8 0.0 0.0 0.0 Aeron, Arth 0.0 0.0 0.0 0.0 0.3 0.4 0.5 0.0 1.4 0.0 Teifi 0.0 0.2 16.2 0.0 0.1 85.8 2.0 0.0 1.0 0.0 N. Pem bs 0.3 0.0 2.2 0.0 0.0 0.5 0.0 0.0 0.2 0.0 Cleddau 0.1 0.0 73.9 0.0 0.2 0.0 50.7 0.0 0.4 0.0 S . Pem bs 1.2 0.0 1.2 0.0 0.0 0.0 0.8 0.0 0.0 0.0 Taf 0.0 0.0 0.0 0.0 2,2 0.0 1.3 0.0 0.5 0.0 Gwendraeth 0.0 0.0 0.0 0.0 0.2 0.0 0.0 0,0 0.0 0.0 Upper Tywi 0.0 0.0 32.2 0.0 0.7 0.0 0.0 0.0 0.2 0.0 Cothi 0.0 0.0 0.2 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Gwili 0.0 0.0 156.7 0.0 0.3 0.0 0.9 0,0 0.0 0.0 Gower 0.0 0.0 40.4 0.0 4.0 0.0 15.9 0,0 0.6 0.0 Loutfior 0.0 0.0 4.7 0.0 0.3 0.0 0.0 0.0 0.0 0.0 Tawe 0.0 0.0 0.0 0.0 11.6 0.0 1.3 0.0 0.0 0.0 Neath 0.0 0.0 13.8 0.0 17.8 82.5 0.0 0.0 0.0 0.0 Afan, Kenfig 0.0 0.0 0.0 0.0 181.6 0.0 0.0 0.0 0.0 0.0 Ogmore 0.0 0.0 5.5 0.0 5.5 0.0 0.0 0.0 0.4 0.0 Thaw 0.0 0.0 0.0 0.0 2.1 0.0 0.0 0.0 0.0 0.0 Ely 0.0 0.0 0.3 0.0 5.7 0.0 0.0 0.0 0.0 0.0 Taff 0.0 0.0 191.6 0.0 7.0 0.0 9.1 0.0 0.9 0.0 Rhymney 0.1 0.0 10.1 0.0 1.8 0.0 2.8 0.0 0.1 0.0 Ebbw 0.0 0.0 23.3 0.0 8.5 0.0 0.0 0.0 20.4 0.0 upper U$K 0.0 0.0 109.5 0.0 0.3 0.0 1.1 0.0 0.0 0.0 Lower Usk 0.1 0.0 191.8 0.0 1.1 0.0 10.0 0.0 0.9 0.0 Upper Wye 0.0 0.0 259.6 0.0 0.0 0.0 3.6 0.0 0.4 0.0 Lower Wye 1.8 0.2 162.8 0.0 6.8 0.0 0.6 0.0 0.2 0.0 Lugg 0.8 0.0 1.8 0.0 0.5 0.0 7.0 0.0 0.1 0.0 Monnow 0.4 0.1 0.0 0.0 0.0 0.0 11.4 0.0 0.0 0.0 Use total 6.3 0.7 2007.0 0.4 268.0 218.2 0.9 31.4 0.9 Whole or part of sub-catchm ent licence-exempt Categories of use 1 Spray Irrigation 2 Agriculture 3 Public water supply 4 Private water supply 5 Industrial 6 HEP 7 Fish farming 8 Electricity—cooling 9 Amenity/Conservation 10 Others C:\JOBS\4432\SUMANALLwk1 F2 14-Jun-94 APPENDIX G PWS DEMAND FORECASTS FOR SUPPLY ZONES WRWRS.REP/75F/27 June 1994 Table G.1 PWS peak week low growth demand forecast ^Pidp£rtBSi6ift mmmm. mmsom wmmas SSSS&SOt}? M S H tU ft m m xu i Southern CUA 1221318 54a 2 487.5 460.6 431.5 435.5 4 4 5 5 456.7 467.9 Monmouth 11257 4.3 4.5 4.2 4.0 4.0 4.1 4.2 4.3 Hereford CUA 102603 52.7 41.0 38.7 36.3 36.6 37.4 38.4 39.3 Whitbome 8566 6.6 3.4 3.2 3.0 3.1 3.1 3.2 3.3 Leintwardine 1140 1.0 0.5 0.4 0.4 0.4 0.4 0.4 0.4 Alton Cout/S.T. Supply 16896 11.3 6.7 6.4 6.0 6.0 6.2 6.3 6.5 Vowchurch & Dorslone 6602 3.1 3.4 3.2 3.0 3.1 3.1 3.2 3.3 Portis/Grecon boreholes 10043 5.8 4.0 3.8 3.5 3.6 3.7 3.6 3.8 Llyswen/Uandeilo Grab an 5595 4.0 2.2 2.1 2.0 2.0 2.0 2.1 2.1 Harley Valtey/Pilleth&FairweU 6624 4.1 2.7 2.6 2.4 2.4 2.5 2.6 2.6 Elan CUA 14079 8.8 5.6 5.3 5.0 5.0 5.1 5.3 5.4 POTABLE TOTAL 1406921 647.1 561.5 5 3 0 6 497.1 501.7 513.2 526.1 539.0 S. CUA NON - POTABLE 98.7 70.3 70.30 70.30 70.30 70.30 70.30 70.30 i 1 I ■ff: s I I rem os. 118322 45.5 47.2 44.6 41.6 42.2 43.2 44.2 45.3 North Ceredigion 22251 10.6 8.9 6.4 7.9 7.9 8.1 8.3 8.5 Mid&S. Ceredigion 57255 26.1 22.9 21.6 20.2 20.4 20.9 21.4 21.9 Felindre/SchwyM 601302 310.7 240.0 226.8 212.5 214.4 219.3 224.8 230.4 Tonn 2514 0.7 1.0 0.9 0.9 0.9 0.9 0.9 1.0 Ystradfellte 62625 15.2 25.0 23.6 22.1 22.3 22.8 23.4 24.0 POTABLE TOTAL 664269 409.0 345.0 325.9 305.4 306.2 315.3 323.2 331.1 Pembs. non-potable 37.3 29.6 29.6 29.6 29.6 29.6 29.6 29.6 Felindre non-potable 4.4 4.4 4.4 4.4 4.4 4.4 4.4 4.4 NON-POTABLE TOTAL 41.7 34.0 34.0 34.0 34.0 34.0 34.0 34.0 i H P B H a i i l i M WMtiaiiaii m m m iO w M «ia m m m m . m m m . m m sm wmzom North Eryri/Ynys Mon 123662 65.3 49.4 46.6 43.7 44.1 45.1 46.2 47.4 Nant Peris 120 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Cwmystradl lyn/Dolbenmaen 21008 12.5 8.4 7.9 7.4 7.5 7.7 7.9 8.0 Llyn Cynwch 3388 2.1 1.4 1.3 1.2 1.2 1.2 1.3 1.3 Barmouth Junction 702 0.6 0.3 0.3 0.2 0.3 0.3 0.3 0.3 Bontddu 231 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Penybont 3538 2.6 1.4 1.3 1.3 1.3 1.3 1.3 1.4 Ganegllwyd 6134 2.9 2.4 2.3 2.2 2.2 2.2 2.3 r 2.3 Gilfor 5833 3.1 2.3 2.2 2.1 2.1 2.1 2.2 2.2 Rhiwgoch 2015 1.5 0.8 0.8 0.7 0.7 0.7 0.8 0.8 Llyn Bodlyn 3969 2.2 t.6 1.5 1.4 1.4 1.5 1.5 1.5 Y Gaer 1042 1.1 0.4 0.4 0.4 0.4 0.4 0.4 0.4 Dinas Mawddwy 421 0.2 0.2 0.2 0,1 0.2 0.2 0.2 0.2 Conis/Pennal 732 0.4 0.3 0.3 0.3 0.3 0.3 0.3 0.3 Abergynofwyn 170 0.2 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Betws y Coed 540 1.1 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Dolwyddelan 261 0.3 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Capet Curig 451 0.3 0.2 0.2 0.2 0.2 0.2" 0.2 0.2 POTABLE TOTAL 174237 96.5 69.5 65.7 61.6 62.1 63.6 65.2 66.7 PWRCYMfitf .. ■ ' 060)91**.$$$ N orthern division m w m m \ Demand - *996; ■ 2001 2006' %mSM& m m sm - Llantairfechan 4170 1.5 1.7 1.6 1.5 1.5 1.5 1.6 1.6 Alwen/Bretton 142696 60.8 57.0 53.8 50.4 50.9 52.1 53.4 54.7 Cowlyd 79400 34.2 31.7 29.9 28.1 28.3 29.0 29.7 30.4 Uyn Conwy 6255 3.7 2.5 2.4 2.2 2.2 2.3 2.3 2.4 Llyn Arenig Fawr 3566 2.3 1.4 1.3 1.3 1.3 1.3 1.3 1.4 Glasgoed/T recastell 76485 35.5 30.5 26.8 27.0 27.3 27.9 28.6 29.3 POTABLE TOTAL 312573 136.0 124.8 117.9 110.4 111.5 114.0 116.9 119.7 NON-POTABLE TOTAL 55.5 33.3 33.3 33.3 33.3 33.3 33.3 33.3 " .■ ' ;Epp*klJp*» gtSterroncf -.vi' Hi mmmm mm&m mmmm wm&m- mm&om P potxaiew ft: ...... 2757999.7 1291 1100.8 1040 974 984 1006 1031 1057 NON-POTABLE TOTAL 196 137.6 137.6 137.6 137.6 137.6 137.6 137.6 ■Pvs^matx. SNMSMtHS SiOwiarfci mmm mm&m * 2 0 0 6 ; MW3&M TOTAL 148020.0 53.8 47.4 49.0 49.9 50.8 51.6 52.4 53.2 w w y\f S v .% v .v .^ .* ^* 1vr& V dv.v.^\^v>.vkvw !v C:\JOBS\443aPWS.WK3 G1 24 —Jun—94 Table G.2 PWS peak week medium growth demand forecast 1 fi I m&Mtm m m m $©ema*>d ' mn&. m m m mmxm wm&am mmxtn Southern CUA 1221310 543.2 487.5 462.4 458.3 458.5 47Z3 487.4 5026 Monmouth 11257 4.3 4.5 4.3 4.2 4.2 4.4 4.5 4.6 Hereford CUA 102603 52.7 41.0 38.8 38.5 38.5 39.7 40.9 42.2 W hit borne 8566 8.8 3.4 3.2 3.2 3.2 3.3 3.4 3.5 Leintwardine 1140 1.0 0.5 0.4 0.4 0.4 0.4 0.5 0.5 Alton Coirt/S.T. Supply 16896 11.3 6.7 6.4 6.3 6.3 6.5 6.7 7.0 Vowchurch & Dorstone 8602 3.1 3.4 3.3 3.2 3.2 3.3 3.4 3.5 Portis/Brecon boreholes 10043 5.8 4.0 3.8 3.8 3.8 3.9 4.0 4.1 Uyswen/Llandeilo Grab an 5595 4.0 2.2 2.1 2.1 2.1 2.2 2.2 2.3 Harley Valley/Pilleth&Fairwell 6824 4.1 2.7 2.6 2.6 2.6 2.6 2.7 2.8 Elan CUA 14079 8.8 5.6 5.3 5.3 5.3 5.4 5.6 5.8 POTABLE TOTAL 1406921 647.1 561.5 532.6 528.0 528.2 544.1 561.5 579.0 S. CUA NON- POTABLE 98.7 70.3 72.00 76.20 81.20 86.20 91.20 96.20 i p i p i i p i W m m ias ■ H wmxtw Pemos. 118322 45.5 47.2 44.8 44.4 44.4 45.8 47.2 48.7 North Ceredigion 22251 10.8 8.9 8.4 8.4 8.4 • 8.6 8.9 9.2 Mid&S. Ceredigion 57255 26.1 22.9 21.7 21.5 21.5 22.1 22.8 23.6 Felindre/Schwytl 601302 310.7 240.0 227.6 225.7 225.7 232.5 240.0 247.5 Tonn 2514 0.7 1.0 1.0 0.9 0.9 1.0 1.0 1.0 Ystradf elite 62625 15.2 25.0 23.7 23.5 23.5 24.2 25.0 25.8 POTABLE TOTAL 864269 409.0 345.0 327.20 324.34 324.45 334.24 344.91 355.67 Pembs. non-potable 37.3 29.6 29.60 29.60 29.60 29.60 29.60 29.60 Felindre non-potable 4.4 4.4 4.40 4.40 4.40 4.40 4.40 4.40 NON-POTABLE TOTAL 41.7 34.0 34.00 34.00 34.00 34.00 34.00 34.00 mmmmmmsmwmmwm m m m mmom. mms&Mwmmm mmsxm mmtm wmmm North Eryri/Yny9 Mon 123662 65.3 49.4 46.8 46.4 46.4 47.8 49.4 50.9 Nart Peris 120 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Cwmystradllyn/Dolbenmaen 21008 12.5 8.4 8.0 7.9 7.9l 8.1 8.4 8.6 Llyn Cynwch 3388 2.1 1.4 1.3 1.3 1.3 1.3 1.4 1.4 Barmouth Junction 702 0.6 0.3 0.3 0.3 0.3 0.3 0.3 0.3 Bontddu 231 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Penybont 3538 2.6 1.4 1.3 1.3 1.3 1.4 1.4 1.5 Ganegllwyd 6134 2.9 2.4 2.3 2.3 2.3 2.4 2.4 2.5 Gil for 5833 3.1 2.3 2.2 2.2 2.2 2.3 2.3 2.4 Rhiwgoch 2015 1.5 0.8 0.8 0.8 0.8 0.8 0.8 0.8 Llyn Bodlyn 3989 2.2 1.6 1.5 1.5 1.5 1.5 1.6 1.6 Y Gaer 1042 1.1 0.4 0.4 0.4 0.4 0.4 0.4 0.4 Dinas Mawddwy 421 0.2 0,2 0.2 0.2 0.2 0.2 0.2 0.2 Coms/Pen nal 732 0.4 0.3 0.3 0.3 0.3 0.3 0.3 0.3 Abergynohvyn 170 0.2 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Betws y Coed 540 1.1 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Dolwyddelan 261 0.3 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Capet Curig 451 0.3 0.2 0.2 0.2 0.2 0.2 0.2 0.2 POTABLE TOTAL 174237 96.5 69.5 66.0 65.4 65.4 67.4 69.5 71.7 OWBCYtffiW - NORTHERN DIVISION fE) . " ■ YW0& 2001 wm 20*1 2016 2021 Llanfairfechan 4170 1.5 1.7 1.6 1.6 1.6 1.6 1.7 1.7 Atwen/Bretton 142696 60.8 57.0 54.0 53.6 53.6 55.2 56.9 58.7 Cowlyd 79400 34.2 31.7 30.1 29.8 29.8 30.7 31.7 32.7 Llyn Conwy 6255 3.7 2.5 2.4 2.3 2.3 2.4 2.5 2.6 Llyn Arenig Fawr 3568 2.3 1.4 1.4 1.3 1.3 1.4 1.4 1.5 Gtasgoed/T recastell 76485 35.5 30.5 29.0 28.7 28.7 29.6 30.5 31.5 POTABLE TOTAL 312573 138.0 124.8 118.3 117.3 117.3 120.9 124.7 128.6 NON-POTABLE TOTAL 55.5 33.3 33.30 33.30 33.30 33.30 33.30 33.30 bwasYMfctmtAt : :U*mend mm&m mm#QQ$wmmm m m m ■pOTAB^TOTAL...... 2758000 1291 1100.8 1044 1035 1035 1067 1101 1135 NON - POTABLE TOTAL 196 137.6 139 144 149 154 159 164 WEDWC ' Pcputettor W m & Q S TOTAL 148020.0 53.8 47.4 49.5 51.0 ( 52.6 54.2 55.7 57.3 CWC . Poet/tefcor YtefcS:Vi. Demand .!$S*X2O0l;|x&¥*a C:\JOBS\443aPWS.WK3 G2 24 —Jun-94 Table G.3 PWS peak week high growth demand forecast .* * *• , ,** . S f e W * Dfemand • **;2 0 D J mmsom. - a o t a Southern CUA 1221318 543.2 487.5 487.9 490.0 511.1 5 3 3 .6 55 6.6 5 8 0 .2 Monmouth 11257 4.3 4.5 4.5 4.5 4.7 4.9 5.1 5 .3 Hereford CUA 102603 52.7 41.0 41.0 41.2 42.9 44.8 46.8 48 .7 W hitbome 8566 8.8 3.4 3.4 3.4 3.6 3.7 3.9 4.1 Leintwardine 1140 1.0 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Alton Coirt/S.T. Supply 16896 11.3 6.7 6.7 6 .8 7.1 7.4 7.7 8 .0 Vowchurch & Derstone 8602 3.1 3.4 3.4 3.5 3.6 3.8 3.9 4.1 Portis/Brecon boreholes 10043 5.8 4.0 4.0 4 .0 4.2 4.4 4.6 4 .8 Llyswen/Uandeilo Grab on 5595 4.0 2.2 2.2 2.2 2.3 2.4 2.5 2.7 Harley Valley/Pilleth& Fa'rwell 6824 4.1 2.7 2.7 2.7 2.9 3.0 3.1 3 .2 Elan CUA 14079 8.8 5.6 5.6 5.6 5.9 6.2 6.4 6 .7 POTABLE TOTAL 1406921 647.1 56 1.5 5 6 2 0 564.4 588.8 614.6 641.2 668.3 S . C U A N O N -P O T A B L E 98 .7 7 0 .3 73.7 78.7 83.7 88.7 93.7 98.7 i0esel#T9!;1005fi m m m ttti: l i l M j i mmsom Pem Ds. 118322 45 .5 47.2 47.3 47.5 49.5 51.7 53.9 56.2 North Ceredigion 22251 10.6 8.9 8.9 6.9 9.3 9.7 10.1 10.6 Mid&S. Ceredigion 57255 26.1 22.9 22.9 23.0 24.0 25.0 26.1 27.2 Felindre/Schwyll 601302 310.7 240.0 24a 2 241.2 251.6 2 6 2 7 2 7 4 .0 28 5.6 Tonn 2514 0.7 1.0 1.0 1.0 1.1 1.1 1.1 1.2 Ystradf elite 62625 15.2 25 .0 25 .0 25.1 26.2 27.4 28.5 29 .7 POTABLE TOTAL 864269 409.0 345.0 345.3 346.7 361.7 377.6 393.9 410.6 Pembs. non-potable 37 .3 29.6 30.7 32.0 33.3 34.6 36.0 37 .3 Felindre non-p o tab le 4.4 4.4 4.4 4.4 4.4 4.4 4.4 4 .4 NON - P O T A B LE T O TA L 41.7 34.0 35.1 36.4 37.7 39.0 40.4 41.7 sfcoptirtaifow mmm® wmmm 1 l '*** igssiSOOBi; m m xm w m m ». North Eryri/Ynys Mon 123662 65.3 49.4 49.4 49.6 51.7 54.0 56.4 58.7 Nant Peris 120 o.il 0.0 0.0 0.0 0.1 0.1 0.1 0.1 Cwmystradllyn/Dotben maen 21008 12.5 6.4 8.4 8.4 8.8 9.2 9.6 10.0 Llyn Cynwch 3388 2.1 1.4 1.4 1.4 1.4 1.5 1.5 1.6 Barmouth Junction 702 0.6 0.3 0.3 0.3 0.3 0.3 0.3 0.3 Bontddu 231 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Penybont 3538 2.6 1.4 1.4 1.4 1.5 1.5 1 6 1.7 Garreqllwyd 6134 2.9 2.4 2.5 2.5 2.6 2 .7 2.8 2.9 Gilfor 5833 3.1 2.3 2.3 2.3 2.4 2.5 2.7 2.8 Rhiwgoch 2015 1.5 0.8 0.8 0.8 0.8 0.9 0.9 1.0 Llyn Bodlyn 3969 2.2 1.6 1.6 1.6 1.7 1.7 1.8 1.9 Y G aer 1042 1.1 0.4 0.4 0.4 0.4 0 .5 0.5 0.5 Dinas Mawddwy 421 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Corris/Pennal 732 0.4 0.3 0.3 0.3 0.3 0.3 0.3 0.3 Abergynolwyn 170 0.2 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Betws y Coed 540 1.1 0.2 0.2 0.2 0.2 0 .2 0.2 0.3 Dolwyddelan 261 0.3 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Capel Curig 451 0.3 0.2 0.2 0.2 0.2 0 .2 0 .2 0.2 POTABLE TOTAL 174237 OR 5 69.5 69.6 69.9 72.9 76.1 79.4 82.8 D W R C Y M R U ' mm NORTHERN DIVISION m wm*m Dem and *096-: •:;.%'.v200e wm m m Llanfairfechan 4170 1.5 1.7 1.7 1.7 1.7 1.8 1.9 2.0 Alwen/Bretton 142696 60.8 57.0 57.0 57.2 59.7 62.3 65.0 67.8 Cowlyd 79400 34.2 31.7 31.7 31.9 33.2 34.7 36.2 37 .7 Llyn Conwy 6255 3.7 2.5 2.5 2.5 2.6 2.7 2.9 3.0 Llyn Arenig Fawr 3568 2.3 1.4 1.4" 1.4 1.5 1.6 1.6 1.7 Glasgoed/T recaste It 76485 35.5 30.5 30.6 30.7 32.0 33.4 34.9 36.3 POTABLE TOTAL 312573 138.0 124.8 124.9 125.4 130.8 136.6 142.5 1 4 a 5 N O N -P O T A B L E T O TA L 55.5 33.3 36.4 40.2 44.0 47.8 51.7 55.5 ...... Baaami&Z ■ ■ Dwfaf*MMSAfc W PopyJatkHt ' 1996 3QQJ • 200ft « 0 M : - m m m 'POTASl ETOTAL 2758000 1291 1100.8 1102 1106 1154 1205 1257 1310 NON-POTABLE TOTAL 196 137.6 145 155 165 176 186 196 WEDWC B a » lh * e %W2 06mandn{hti/<& y • w C*wrnwVd ...... tse fc ' - W l ' l ...... 20 06 W& 3Q iM : "'"".'PS TOTAL 148020.0 53.8 47.4 50.1 51.51 55 .2 5 7 .8 60 .2 62 .2 o w e " " ■ •. •. oenvm ct :J>opt/tedk>n Y)eW Dem and 2 0 0 1 | 2 0 0 8 wmzam S:si;i20ZI:: TOTAL 107100.0 34.6 32.4 34.5 3 6 .8 1 39.7 42.8 45 .6 47 .6 C:\JOBS\4432\PWS.WK3 G3 24 —Jun —94 Table G.4 Peak week marginal demands — Low growth forecast tfarginai DomandW ' ' ' ' * '' :..... -...... :...... ; .. V ***■ 1996 \2001i ^ 2006 2Q21 Southern CUA 0.0 0.0 0.0 0.0 0.0 0.0 Monmouth 0.0 0.0 0.0 0.0 0.0 0.0 Hereford CUA 0.0 0.0 0.0 0.0 0.0 0.0 Whit borne 0.0 0.0 0.0 0.0 0.0 0.0 Leintwardine 0.0 0.0 0.0 0.0 0.0 0.0 Alton Court/S.T. Supply 0.0 0.0 0.0 0.0 0.0 0.0 Vowchurch & Dorstone 0.1 0.0 0.0 0.0 0.1 0.2 Portis/Brecon boreholes 0.0 0.0 0.0 0.0 0.0 0,0 Llyswen/Llandeilo Graban 0.0 0.0 0.0 0.0 0.0 0.0 Harley Valley/Pilleth&Fairwell 0.0 0.0 0.0 0.0 0.0 0.0 Elan CUA 0.0 0.0 0.0 0.0 0.0 0.0 DIVISION TOTAL 0.1 0.0 0.0 0.0 0.1 0.2 H i l l ® m m m m wmmm®wmmm wmmm i i l i i i i l M S S Pem bs. 0.0 0.0 0.0 0.0 0.0 0.0 North Ceredigion 0.0 0.0 0.0 0.0 0.0 0.0 Mid&S. Ceredigion 0.0 0.0 0.0 0.0 0.0 0.0 Felindre/Schwyll 0.0 0.0 0.0 0.0 0.0 0.0 Tonn 0.2 0.2 0.2 0.2 0.2 0.3 Ystradfellte 8.4 6.9 7.1 7.6 8.2 8.8 DIVISION TOTAL 8.7 7.1 7.3 7.9 8.5 9.1 DW R CYM RU N (W OIV»aOM 111 ...... I 'i l l ! ll§lt,,,,,.1Q96 mm m m m m i i M 1 t ■ 'm m wmmm North Eryri/Ynys Mon 0.0 0.0 0.0 0.0 0.0 0.0 Nant Peris 0.0 0.0 0.0 0.0 0.0 0.0 Cwmystradllyn/Dolbenmaen 0.0 0.0 0.0 0.0 0.0 0.0 Llyn Cynwch 0.0 0.0 0.0 0.0 0.0 0.0 Barmouth Junction 0.0 0.0 0.0 0.0 0.0 0.0 Bontddu 0.0 0.0 0.0 0.0 0.0 0.0 Penybont 0.0 0.0 0.0 0.0 0.0 0.0 Garregllwyd 0.0 0.0 0.0 0.0 0.0 0.0 Gilfor 0.0 0.0 0.0 0.0 0.0 0.0 Rhiwgoch 0.0 0.0 0.0 0.0 0.0 0.0 Llyn Bodlyn 0.0 0.0 0.0 0.0 0.0 0.0 Y Gaer 0.0 0.0 0.0 0.0 0.0 0.0 Dinas Mawddwy 0.0 0.0 0.0 0.0 0.0 0.0 Corris/Pennal 0.0 0.0 0.0 0.0 0.0 0.0 Abergynolwyn 0.0 0.0 0.0 0.0 0.0 0.0 Betws y Coed 0.0 0.0 0.0 0.0 0.0 0.0 Dolwyddelan 0.0 0.0 0.0 0.0 0.0 0.0 Capel Curig 0.0 0.0 0.0 0.0 0.0 0.0 DIVISION TOTAL 0.0 0.0 0.0 0.0 0.0 0.0 DWfc CYM RU N (E) DIVISIO N. .|:g: jivi-: -i-: PO D 1 -'Mf* Llanfairfechan 0.1 0.0 0.0 0.0 0.1 0.1 Alwen/B retton 0.0 0.0 0.0 0.0 0.0 0.0 Cowlyd 0.0 0.0 0.0 0.0 0.0 0.0 Llyn Conwy 0.0 0.0 0.0 0.0 0.0 0.0 Llyn Are nig Faw r 0.0 0.0 0.0 0.0 0.0 0.0 Glasgoed/T recaste II 0.0 0.0 0.0 0.0 0.0 0.0 DIVISION TOTAL 0.1 0.0 0.0 0.0 0.1 0.1 W ED W C. Marqinal.D&nrtand (Mi/d) 1996 : 2001 ;::2006 201-1 ■•^ 02018. 2021 Total 0.0 0.0 0.0 0.0 0.0 0.0 ' CWC Marginal Dem and (to, M ...... 1996 2001 2006 ' , 2011 2016 ' 2021 Total 0.0 0.5 2.2 4.0 5.6 7.4 REGION TOTAL 9 8 10 12 14 17 C:\JOBS\4432\PWS.WK3 G4 24-Jun Table G.5 Peak week marginal demands — Medium growth forecast mmmm ■ a n mmmm Southern CUA 0.0 0.0 0.0 0.0 0.0 0.0 Monmouth 0.0 0.0 0.0 0.1 0.2 0.3 Hereford CUA o.oj 0.0 0.0 0.0 0.0 0.0 Whitbome 0.0 0.0 0.0 0.0 0.0 0.0 Leintwardine 0.0 0.0 0.0 0.0 0.0 0.0 Alton Court/S.T. Supply 0.0 0.0 0.0 0.0 0.0 0.0 Vowchurch & Dorstone 0.2 0.1 0.1 0.2 0.3 0.4 Portis/Brecon boreholes 0.0 0.0 0.0 0.0 0.0 0.0 Llyswen/Llandeilo Graban 0.0 0.0 0.0 0.0 0.0 0.0 Harley Valtey/Pilleth&Fairwell 0.0 0.0 0.0 0.0 0.0 0.0 Elan CUA 0.0 0.0 0.0 0.0 0.0 0.0 DIVISION TOTAL 0.2 0.1 0.1 0.3 0.5 0.8 dwr cwpu s,w. splsSfpimmmmmmmmmm M i i i i i l mmmmmwmmm l i S I & i i ; mmmm Pembs. 0.0 0.0 0.0 0,3 1.7 3.2 North Ceredigion 0.0 0.0 0.0 0.0 0.0 0.0 Mid&S. Ceredigion 0.0 0.0 0.0 0.0 0.0 0.0 Felindre/Schwyll 0.0 0.0 0,0 0.0 0.0 0.0 Tonn 0.3 0.2 0.2 0.3 0.3 0.3 Ystradf elite 8.5 8.3 8.3 9.0 9.8 10.6 DIVISION TOTAL 8.8 8.5 8.6 9.5 11.8 14.1 DWR CYMRU N{W).OtVlSION ■...... Ililie ilP * • ' warn mmmm wmmm. mmmm :' " 2 9 1$ North Eryri/Ynys Mon 0.0 0.0 0.0 0.0 0.0 0.0 Nant Peris 0.0 0.0 0.0 0.0 0.0 0.0 C wmystrad 1 lyn/D ol ben m aen 0.0 0.0 0.0 0.0 0.0 0.0 Llyn Cynwch 0.0 0.0 0.0 0.0 0.0 0.0 Barmouth Junction 0.0 0.0 0.0 0.0 0.0 0.0 Bontddu 0.0 0.0 0.0 0.0 0.0 0.0 Penybont 0.0 0.0 0.0 0.0 0.0 0.0 Garreqllwyd 0.0 0.0 0.0 0.0 0.0 0.0 Gilfor 0.0 0.0 0.0 0.0 0.0 0.0 Rhiwgoch 0.0 0.0 0.0 0.0 0.0 0.0 Llyn Bodlyn 0.0 0.0 0.0 0.0 0.0 0.0 Y G a e r 0.0 0.0 0.0 0.0 0.0 0.0 Dinas Mawddwy 0.0 0.0 0.0 0.0 0.0 0.0 Corris/Pennal 0.0 0.0 0.0 0.0 0.0 0.0 Abergynolwyn 0.0 0.0 0.0 0.0 0.0 0.0 Betws y Coed 0.0 0.0 0.0 0.0 0.0 0.0 Dolwyddelan 0.0 0.0 0.0 0.0 0.0 0.0 Capel Curig 0.0 0.0 0.0 0.0 0.0 0.0 DIVISION TOTAL 0.0 0.0 0.0 0.0 0.0 0.0 DWR CYMRU N p ) €»V)SION Marginal DamartcMMl 1996 2001 2006 2011 ., 2oie ' .2021 Llanfairfechan 0.1 0.1 0.1 0.1 ' 0.2 0.2 Alwen/Brett on 0.0 0.0 0.0 0.0 0.0 0.0 Cowlyd 0.0 0.0 0.0 0.0 0.0 0.0 Uyn Conwy 0.0 0.0 0.0 0.0 0.0 0.0 Llyn Areniq Fawr 0.0 0.0 0.0 0.0 0.0 0.0 Glasqoed/T reeastell 0.0 0.0 0.0 0.0 0.0 0.0 DIVISION TOTAL 0.1 0.1 0.1 0.1 0.2 0.2 WEDWG - ■ . ■ : • Marginal Demand (Ml 1996 2001 2006 5011 s o ie * 2021 Total 0.0 0.0 0.0 0.4 1.9 3.5 6WC - .. n . MarQjnatDemaWMlm. • ' 1996 2001 2006.; m 201$ 20211 Total 0.0 1.0 3.1 5.3 7.4 9.7 REGION TOTAL 9 10 12 16 2 2 | 28 C:\JOBS\4432\PWS.WK3 G5 2 4 —Ju n —94 Table G.6 Peak week marginal demands — High growth forecast DWR.CYMBU S .E, DIVISION !' \ .:?■ 1996 iiiisso o fc m $ a n : 2Q21 Southern CUA 0.0 0.0 0.0 0.0 13.4 37.0 Monmouth 0.2 0.2 0.4 0.6 0.8 1.0 Hereford CUA 0.0 0.0 0.0 0.0 0.0 0.0 Whit borne 0.0 0.0 0.0 0.0 0.0 0.0 Leintwardine 0.0 0.0 0.0 0.0 0.0 0.0 Alton Court/S.T. Supply 0.0 0.0 0.0 0.0 0.0 0.0 Vowchurch & Dorstone 0.3 0.4 0.5 0.7 0.8 1.0 Portis/Brecon boreholes 0.0 0.0 0.0 0.0 0.0 0.0 Llyswen/Uandeilo Graban 0.0 0.0 0.0 0.0 0.0 0.0 Harley VaHey/Pilleth&Fairwell 0.0 0.0 0.0 0.0 0.0 0.0 Elan CUA 0.0 0.0 0.0 0.0 0.0 0.0 DIVISION TOTAL 0.5 0.6 0.9 1.3 15.0 39.0 DWR CYMBtS S,W. DIVISION ^ *n v'lll 199$ ' ' mm !ill£ Q 0 6 - £&r-!80S1 ' m m '' 20 21 Pembs. 1.8 2.0 4.0 6.2 8.4 10.7 North Ceredigion 0.0 0.0 0.0 0.0 0.0 0.0 Mid&S. Ceredigion 0.0 0.0 0.0 0.0 0.0 1.1 Felindre/Schwyll 0.0 0.0 0.0 0.0 0.0 0.0 Tonn 0.3 0.3 0.4 0.4 0.4 0.5 Ystradfellte 9.8 9.9 11.0 12.2 13.3 14.5 DIVISION TOTAL 11.9 12.2 15.4 18.7 22.2 26.9 DWR CYMRU N(W> DIVISION i' ' : ' M iiliiliP 1996 2001 m m w m n i M m m m m North Eryri/Ynys Mon 0.0 0.0 0.0 0.0 0.0 0.0 Nant Peris 0.0 0.0 0.0 0.0 0.0 0.0 Cwmystradllyn/Dolbenmaen 0.0 0.0 0.0 0.0 0.0 0.0 Llyn Cynwch 0.0 0.0 0.0 0.0 0.0 0.0 Barmouth Junction 0.0 0.0 0.0 0.0 0.0 0.0 Bontddu 0.0 0.0 0.0 0.0 0.0 0.0 Penybont 0.0 0.0 0.0 0.0 0.0 0.0 Garregllwyd 0.0 0.0 0.0 0.0 0.0 0.0 Gilfor 0.0 0.0 0.0 0.0 0.0 0.0 Rhiwgoch 0.0 0.0 0.0 0.0 0.0 0.0 Llyn Bodlyn 0.0 0.0 0.0 0.0 0.0 0.0 Y G aer 0.0 0.0 0.0 0.0 0.0 0.0 Dinas Mawddwy 0.0 0.0 0.0 0.0 0.0 0.0 Corris/Pennal 0.0 0.0 0.0 0.0 0.0 0.0 Abergynolwyn 0.0 0.0 0.0 0.0 0.0 0.0 Betws y Coed 0.0 0.0 0.0 0.0 0.0 0.0 Dolwyddelan 0.0 0.0 0.0 0.0 0.0 0.0 Capel Curig 0.0 0.0 0.0 0.0 0.0 0.0 DIVISION TOTAL 0.0 0.0 0.0 0.0 0.0 0.1 DWR CYMRU N(E) DIVISION Marginal Oamarjd (Mi/d) * . ' 1996 2001 2006 2011 2016 2021 Llanfairfechan 0.2 0.2 0.3 0.3 0.4 0.5 Alwen/Bretton 0.0 0.0 0.0 1.6 4.2 7.0 Cowlyd 0.0 0.0 0.0 0.5 2.0 3.5 Llyn Conwy 0.0 0.0 0.0 0.0 0.0 0.0 Llyn Arenig Fawr 0.0 0.0 0.0 0.0 0.0 0.0 Glasgoed/T recastell 0.0 0.0 0.0 0.0 0.0 0.8 DIVISION TOTAL 0.2 0.2 0.3 2.4 6.6 11.8 W ED W C . Marginal Demand (Ml/d) -7 *^ 1 9 9 6 '■'<^:2Q0V•-'■■.32006 2 0 1 1 1 " 2 0 1 6 2021: Total 0.0 0.0 1.4 4.of 6.4 8.4 CWC Margin&:$errfcrtcfc{to WF ...... 1996 2001 2006; m m n 201^ 2021 Total 0.0 2.2 5.1 8.2 11.0 13.0 REGION TOTAL 13 15 23 35 61 99 C:\JOBS\4432\PWS.WK3 G6 2 4 - Ju n -9 4 9 Capyri^tt B tm A Partnor* 0o»« O o t* Not* Th* bnts. Indu&Y) «h* and « p « W o f « 0rva rfwon in T,ac*o Dote: <*o»«rq or» not to bo t<*on a* •m u n g tho a btg ottan * o f «ho Chocks* D o te oantroctor Ifld fr ttn Contract O ot« R»». Notn of >wW» Ona m CHud. Rvwd Ooto. NORTH WEST WATER LTD ■*(<* f t < t m S irv o y UrtoudKXiw d re p rod u ction 1 :1 0 0 0 0 mop «<*> tho up'ni—«>i of »>• Controtar O w i Ccpyrt#* ®id may M to of H r MsiMty't O fHoo.4 Q"~o C ow ri^t pro~ou«on or oM proo—<*^» B M C * PARTNERS n w i. 9umrr Uoanco No. 10M 1 - SOUTVCRN CVA 21 ULYN CYNWCH 2 - MOMOUTH 22 BARMOUTH JUNCTION 3 - HEREFORD CJUA 23 B 0 N T 0 0 U 4 - WHTB0UR»« 24 P EN YB O N T 3 - LEMTWAROTC 25 GARREGLLWYD 6 - ALTON COURT / SEVERN TRENT SUP 2 6 C L P OR 7 - VOWCHURCH & DORSTOC 27 R H W C O C H 8 - P O R TIS Sc B RECO N BO R EH O LES 28 LLYN BOOLYN 9 - LLYSWEN / 9 LLAfCELO GRABAN 29 Y G AER 10 - HARLEY VALLEY / PULETH & FARWELL 30 - DMAS MAWDOWY 11 - ELAN C.UA 31 - CORRS / PEM^AL 12 - PEVBROKESKWE 32 - A8ERCYN0LWYN 13 - N. CEREDOON 33 - LLYN AREMC FAWR 14 — MO 4c S CEREDOON 34 - ALWEN / BRETTON 15 - FELtCRE / SCHWYLL 35 - COWL YD / DULYN 16 - TOM* 36 - LLYN CONWY 17 - YSTRAOFELLTE 37 - LLAhFAPFECHAN 18 - NORTH ERYRI / YNYS MON 38 - BETW S-Y—COED 19 - NANT PERIS 39 - DOLWYOOELAN 2 0 - CWMYSTRADLLYN / DCLBEhMAEN 4 0 _ CAPEL CURIC 41 - CLASGOED / TRECASTELL KEY: Coastline Company Areas: □ Dwr Cymru NRA Welsh Region Boundary Chester Waterworks Co. Water Company Supply Boundaries Wrexham Sc E.Denbighshire □ W ater Co. 11 Dwr Cymru Water Supply Zones SCALE 1 : 1.000.000 9 “W: 1--- 1- NATIONAL RIVERS AUTHORITY (WELSH REGION) Regional Water Resources Strategy Water Company Supply Zones FIGURE G.1 M l M l m. APRL 94 Sote 1:1 .000.000 BINNIE & PARTNERS c«is«tna« iic iic c if &■— j ~ 005*00) HOUSE - DBM1 - M »Tf ♦432/06/01 g44J2dOO/«r«r/bndc KAL <3£VS OCPT 13/4/94 APPENDIX H PRIVATE DEMAND FORECASTS WRWRS.REP/75F/27 June 1994 $ Table H.1 Power generation: HEP demands — low growth forecast Gross average demand (M^d) Subcatchment 1981 1986 1991 1996 2001 2006 2011 2016 1 2021 Anglesey 0.0 0.0 O.TF 0.0 0.0 0.0 0.0 0.0 0.0 Upper Dee 154.8 125.7 265.7 271.9 271.9 271.9 271.9 271.9 271.9 Middle Dee 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Lower Dee 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Clwyd 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Conwy 167.4 135.9 287.5 494.1 494.1 494.1 494.1 494.1 494.1 Gwrfal 58.2 47.3 100.0 102.3 202.3 302.3 302.3 302.3 302.3 Dwyfor 2.1 1.7 3.6 3.6 3.6 3.6 3.6 3.6 3.6 Glaslyn 203.5 165.2 349.4 657.5 957.5 1157.5 1157.5 1157.5 1157.5 Artro, Mawddach 6.9 5.6 11.9 1Z1 12.1 12.1 12.1 12.1 12.1 Dysynnl 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Dyfl, Leri 9.4 7.7 16.2 116.6 116.6 116.6 116.6 116.6 116.6 Rheidol 244.1 198.2 419.1 428.9 428.9 428.9 428.9 428.9 428.9 Aeron, Arth 0.2 0.2 0.4 0.4 0.4 0.4 0.4 0.4 0.4 Tein 51.0 41.4 87.6 89.7 89.7 89.7 89.7 89.7 89.7 N. Pembs 0.3 0.2 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Cleddau 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 S. Pembs 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Taf 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Gwendraeth 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Upper Tywi 0.0 0.0 0.0 340.0 340.0 340.0 340.0 340.0 340.0 Cothl 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Gwlll 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Gower 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Loughor 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Tawe 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Neath 49.1 39.9 84.3 86.2 86.2 86.2 86.2 86.2 86.2 Afan, Kenfig 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Ogmore 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Thaw 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Ely 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Taff 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Rhymney 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Ebbw 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Upper Usk 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Lower Usk 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Upper Wye 0.0 0.0 0.0 300.0 300.0 300.0 300.0 300.0 300.0 Lower Wye 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Lugg 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Monnow 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 COW FORECAST TOTAL 947.2 76570' 1626.2 2903.9 3303.9 3603.9 ~3eoxg_ 3603.91~~300379') c:\jobs\4432\private.wk1 H1 24—Jun —94 Table H.2 Power generation: HEP demands - high growth forecast Gross average demand (Ml/d) Subcatchment 1981 1986 1991 1996 2001 2006 2011 2016 2021 Anglesey 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Upper Dee 154.8 125.7 265.7 271.9 271.9 271.9 271.9 271.9 271.9 Middle Dee 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Lower Dee 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Clwyd 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Conwy 167.4 135.9 287.5 494.1 494.1 494.1 494.1 494.1 494.1 Gwrfal 58.2 47.3 100.0 202.3 402.3 502.3 502.3 502.3 502.3 Dwyfor 2.1 1.7 3.6 103.6 303.6 403.6 403.6 403.6 403.6 Glaslyn 203.5 165.2 349.4 757.5 1057.5 1257.5 1257.5 1257.5 1257.5 Artro, Mawddach 6.9 5.6 11.9 1Z1 12.1 12.1 12.1 121 12.1 Dysynnl 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Dyfl, Leri 9.4 7.7 16.2 116.6 116.6 116.6 116.6 116.6 116.6 Rheidol 244.1 198.2 419.1 428.9 428.9 428.9 428.9 428.9 428.9 Aeron, Arth 0.2 0.2 0.4 0.4 0.4 0.4 0.4 0.4 0.4 Teifi 51.0 41.4 87.6 89.7 89.7 89.7 89.7 89.7 89.7 N. Pembs 0.3 0.2 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Cleddau 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 S . Pembs 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Taf 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Gwendraeth 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Upper Tywi 0.0 0.0 0.0 340.0 340.0 340.0 340.0 340.0 340.0 Cothi 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Gwill 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Gower 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Loughor 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Tawe 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Neath 49.1 39.9 84.3 86.2 86.2 86.2 86.2 86.2 86.2 Afan, Kenfig 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Ogmore 0.0 0.0 0.0 0.0 0.0 0.0 0.0 o;o 0.0 Thaw 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Ely 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Taff 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Rhymney 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Ebbw 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Upper Usk 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Lower Usk 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Upper Wye 0.0 0.0 0.0 300.0 300.0 300.0 300.0 300.0 300.0 Lower Wye 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Lugg 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Mon now 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 IHIGH FORECAST TOTAL 947.2 769.0 1626.2 3203.9 3903.9 4303.9 4303.9 4303.9 4303.9 c:\jobs\4432\private.wk1 H2 24-Jun-94 Table H.3 Industrial demands — low growth forecast Gross average demand (M^d) Subcatchment 1981 1986 1991 1996 2001 2006 2011 20161 2021 Anglesey 0.0 0.0 0.0 070 ■■ 0.0 0.0 0.0 0.0 " 0.0 Upper Dee 0.2 0.2 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Middle Dee 9.6 8.6 4.8 4.6 4.4 4.1 3.9 3.6 3.4 Lower Dee 17.9 16.0 9.1 8.6 8.1 7.7 7.2 6.8 6.3 Clwyd 1.0 0.9 0.5 0.5 0.5 0.4 0.4 0.4 0.4 Conwy 2.1 1.9 1.1 1.0 1.0 0.9 0.9 0.8 0.8 Gwrfal 0.6 0.5 0.3 0.3 0.3 0.2 0.2 0.2 0.2 Dwyfor 3.3 3.0 1.7 1.6 1.5 1.4 1.3 1.3 1.2 Glaslyn 0.1 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Artro, Mawddach 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Dysynnl 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Dyfl, Leri 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.0 Rheidol 0.1 0.1 0.1 0.0 0.0 0.0 0.0 0.0 0.0 Aeron, Arth 0.7 0.6 0.3 0.3 0.3 0.3 ^ .3 0.3 0.2 Teifi 0.3 0.3 0.1 0.1 0.1 0.1 0.1 0.1 0.1 N. Pembs 0.1 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Cleddau 0.4 0.3 0.2 0.2 0.2 0.2 0.1 0.1 0.1 S. Pembs 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Taf 5.2 4.7 2.6 2.5 2.4 2.2 2.1 2.0 1.9 Gwendraeth 0.5 0.5 0.3 0.3 0.2 0.2 0.2 0.2 0.2 Upper Tywi 1.7 1.5 0.8 0.8 0.8 0.7 0.7 0.6 0.6 Colhi 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Gwill 1.2 1.1 0.6 0.6 0.5 0.5 0.5 0.5 0.4 Gower 10.0 9.0 5.1 4.8 4.6 4.3 4.1 3.8 3.5 Loughor 1.3 1.1 0.6 0.6 0.6 0.5 0.5 0.5 0.4 Tawe 27.2 24.3 13.7 13.0 12.4 11.7 11.0 10.3 9.6 Neath 41.7 37.3 21.1 20.0 19.0 17.9 16.9 15.8 14.7 Afan, Kenfig 426.7 381.3 215.4 204.6 193.8 183.1 172.3 161.5 150.8 Ogmore 12.8 11.5 6.5 6.2 5.8 5.5 5.2 4.9 4.5 Thaw 5.2 4.6 2.6 2.5 2.3 2.2 2.1 2.0 1.8 Ely 18.6 16.6 9.4 8.9 8.5 8.0 7.5 7.1 6.6 Taff 21.0 18.7 10.6 10.0 9.5 9.0 8.5 7.9 7.4 Rhymney 6.4 5.7 3.2 3.0 2.9 2.7 2.6 2.4 2.2 Ebbw 24.1 21.5 12.1 11.5 10.9 10.3 9.7 9.1 8.5 Upper Usk 0.6 0.5 0.3 0.3 0.3 0.3 0.2 0.2 0.2 Lower Usk 2.9 2.6 1.5 1.4 1.3 1.3 1.2 1.1 1.0 Upper Wye 0.1 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Lower Wye 16.1 14.4 8.1 7.7 7.3 6.9 6.5 6.1 5.7 Lugg 15.3 13.6 7.7 7.3 6.9 6.5 6.2 5.8 5.4 Monnow 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 LAW FORECAST TOTAL 675.2 603.4 — 3^078" 323.8 306.7 28977" 272761' 255.61” 235751 c:\jobs\4432\private.wk1 H3 24—Jun—94 Table H.4 Industrial demands — high growth forecast Gross average demand (Ml/d) Subcatchment 1981 I 1986! 1991 1996 2001 2006 2011 2016 2021 Anglesey 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Upper Dee 0.2 0.2 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Middle Dee 9.6 8.6 4.8 4.8 4.8 4.8 4.8 4.8 4.8 Lower Dee 17.9 16.0 9.1 9.1 9.1 9.1 9.1 9.1 9.1 Clwyd 1.0 0.9 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Conwy 2.1 1.9 1.1 1.1 1.1 1.1 1.1 1.1 1.1 Gwrfal 0.6 0.5 0.3 0.3 0.3 0.3 0.3 0.3 0.3 Dwyfor 3.3 3.0 1.7 1.7 1.7 1.7 1.7 1.7 1.7 Glaslyn 0.1 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Artro, Mawddach 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Dysynnl, 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Dyfl, Leri 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Rheidol 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Aeron, Arlh 0.7 0.6 0.3 0.3 0.3 0.3 0.3 0.3 0.3 Teifi 0.3 0.3 0.1 0.1 0.1 0.1 0.1 0.1 0.1 N. Pembs 0.1 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Cleddau 0.4 0.3 0.2 0.2 0.2 0.2 0.2 0.2 0.2 S. Pembs 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Taf 5.2 4.7 2.6 2.6 2.6 2.6 2.6 2.6 2.6 Gwendraeth 0.5 0.5 0.3 0.3 0.3 0.3 0.3 0.3 0.3 Upper Tywi 1.7 1.5 0.8 0.8 0.8 0.8 0.8 0.8 0.8 Cothi 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Gwlll 1.2 1.1 0.6 0.6 0.6 0.6 0.6 0.6 0.6 Gower 10.0 9.0 5.1 5.1 5.1 5.1 5.1 5.1 5.1 Loughor 1.3 1.1 0.6 0.6 0.6 0.6 0.6 0.6 0.6 Tawe 27.2 24.3 13.7 13.7 13.7 13.7 13.7 13.7 13.7 Neath 41.7 37.3 21.1 21.1 21.1 21.1 21.1 21.1 21.1 Afan. Kenfig 426.7 381.3 215.4 215.4 215.4 215.4 215.4 215.4 215.4 Ogmore 12.8 11.5 6.5 6.5 6.5 6.5 6.5 6.5 6.5 Thaw 5.2 4.6 2.6 2.6 2.6 2.6 2.6 2.6 2.6 Ely 18.6 16.6 9.4 9.4 9.4 9.4 9.4 9.4 9.4 Taft 21.0 18.7 10.6 10.6 10.6 10.6 10.6 10.6 10.6 Rhymney 6.4 5.7 3.2 3.2 3.2 3.2 3.2 3.2 3.2 Ebbw 24.1 21.5 12.1 12.1 12.1 12.1 12.1 12.1 12.1 Upper Usk 0.6 0.5 0.3 0.3 0.3 0.3 0.3 0.3 0.3 Lower Usk 2.9 2.6 1.5 1.5 1.5 1.5 1.5 1.5 1.5 Upper Wye 0.1 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Lower Wye 16.1 14.4 8.1 8.1 8.1 8.1 8.1 8.1 8.1 Lugg 15.3 13.6 7.7 7.7 7.7 7.7 7.7 7.7 7.7 Mon now 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 IHIGH FORECAST TOTAL I 675.2 | 603.41 340.8 340.8 340.8 340.8 340.8 340.8 340.8 c:\jobs\4432\private.wk1 H4 2 4 -Jun-94 Table H.5 Spray Irrigation demands — low growth forecast Gross average demand (MVd) Subcatchment 1981 1986 1991 1996 2001 2006 2011 2016 1 2021 Anglesey ' 0:0" 0.0 0.0 0.0 0.0 6.0 0.0 0.0 0.0 Upper Dee 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Middle Dee 0.2 0.3 0.4 0.4 0.5 0.5 0.6 0.6 0.7 Lower Dee 0.2 0.4 0.5 0.5 0.6 0.6 0.7 0.7 0.8 Clwyd 0.1 0.1 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Conwy 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Gwrfai 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Dwyfor 0.0 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Glaslyn 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Artro, Mawddach 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Dysynni 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Dyfi. Leri 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Rheidol 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Aeron, Artti 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Teifi 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.1 N. Pembs 0.1 0.2 0.3 0.3 0.3 0.3 0.4 0.4 0.4 Cleddau 0.0 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 S. Pembs 0.5 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 Taf 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Gwendraeth 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Upper Tywi 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Cothi 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Gwili 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Gower 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Loughor 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Tawe 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Neath 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Afan, Kenfig 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Ogmore 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Thaw 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Ely 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Taff 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Rhymney 0.0 0.0 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Ebbw 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Upper Usk 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Lower Usk 0.1 0.1 0.1 0.1 0.2 0.2 0.2 0.2 0.2 Upper Wye 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Lower Wye 0.9 1.5 1.7 2.0 2.2 2.4 2.5 2.7 2.9 Lugg 0.4 0.7 0.8 0.9 1.0 1.1 1.2 1.2 1.3 Monnow 0.2 0.3 0.4 0.4 0.5 0.5 0.6 0.6 0.6 LOW FORECASTTOTAL 31T 4.9 ■ ■ S.T 6.3 7.1 7.7 ' 8 . 2 1 8.8 9.3 c:\jobs\4432\private.wk1 H5 24-Jun-94 Table H.6 Spray Irrigation demands — high growth forecast Gross average demand (Ml/d) Subcatchment 1981 1986 1991 1996 2001 2006 2011 2016 2021 Anglesey 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Upper Dee 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Middle Dee 0.2 0.3 0.4 0.7 0.7 0.8 0.9 0.9 1.0 Lower Dee 0.2 0.4 0.5 0.8 0.9 0.9 1.0 1.1 1.1 Clwyd 0.1 0.1 0.2 0.3 0.3 0.3 0.3 0.4 0.4 Conwy 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 GwrtaJ 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Dwyfor 0.0 0.1 0.1 0.2 0.2 0.2 0.2 0.2 0.2 Glaslyn 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Artro, Mawddach 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Dysynni 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Dyfi, Leri 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Rheidol 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Aeron, Arth 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Teifi 0.0 0.0 0.0 0.1 0.1 0.1 0.1 0.1 0.1 N. Pembs 0.1 0.2 0.3 0.4 0.5 0.5 0.5 0.6 0.6 Cleddau 0.0 0.1 0.1 0.1 0.2 0.2 0.2 0.2 0.2 S . Pembs 0.5 0.8 0.9 1.5 1.7 1.8 2.0 2.1 2.2 Taf 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Gwendraeth 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Upper Tywi 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Cothi 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Gwlli 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Gower 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Loughor 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Tawe 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Neath 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Afan, Kenflg 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Ogmore 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.1 Thaw 0.0 0.0 0.0 0.0 0.0 0.1 0.1 0.1 0.1 Ely 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Taff 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Rhymney 0.0 0.0 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Ebbw 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Upper Usk 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Lower Usk 0.1 0.1 0.1 0.2 0.2 0.2 0.3 0.3 0.3 Upper Wye 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Lower Wye 0.9 1.5 1.7 2.9 3.3 3.5 3.8 4.1 4.3 Lugg 0.4 0.7 0.8 1.3 1.5 1.6 1.7 1.8 2.0 Monnow 0.2 0.3 0.4 0.7 0.7 0.8 0.8 0.9 1.0 IHIGH FORECAST TOTAL 3.0 4.9 5.7 9.5 10.6 11.5 12.4 13.2 14.0 c:\jobs\4432\private.wk1 H6 24-Jun-94 Table H.7 General agriculture demands — low growth forecast Gross average demand (M^d) Subcatchment 1981 1986 1991 1996 2001 2006 2011 2016 2021 Anglesey 0.0 0.0 0.0 0.0 0.0 0.0 0.0 " 0.0 0.0 Upper Dee 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Middle Dee 0.9 0.9 1.1 1.1 1.1 1.1 1.1 1.1 1.1 Lower Dee 1.5 1.5 1.8 1.8 1.8 1.8 1.8 1.8 1.8 Clwyd 0.2 0.2 0.3 0.3 0.3 0.3 0.3 0.3 0.3 Conwy 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Gwrfai 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Dwyfor 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Glaslyn 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Artro, Mawddach 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Dysynnl 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Dyfl, Leri 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Rheidol 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Aeron, Arth 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Teifi 0.3 0.3 0.4 0.4 0.4 0.4 0.4 0.4 0.4 N. Pembs 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Cleddau 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 S. Pembs 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Taf 0.3 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 Gwendraeth 0.1 0.1 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Upper Tywi 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Cothl 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Gwili 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Gower 0.1 0.1 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Loughor 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Tawe 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Neath 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Afan, Kenfig 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Ogmore 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Thaw 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Ely 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Taff 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Rhymney 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Ebbw 0.0 0.0 0.0 0.0 0.0 0,0 0.0 r~ o.o 0.0 Upper Usk 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Lower Usk 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 Upper Wye 0.3 0.3 0.4 0.4 0.4 0.4 0.4 0.4 0.4 Lower Wye 2.1 2.1 2.4 2.4 2.4 2.4 2.4 2.4 2.4 Lugg 3.2 3.3 3.8 3.8 3.8 3.8 3.8 3.8 3.8 Monnow 0.7 0.7 0.8 0.8 0.8 0.8 0.8 0.8 0.8 LOW FORECAST t o t a l 11.0 11.2 12.8 12.8 12.8 12.8 12.8 12.8 12.8 c:\jobs\4432\private.wk1 H7 24-Jun-94 Table H.8 General agriculture demands — high growth forecast Gross average demand (Ml/d) Subcatchment 1981 1986 1991 1996 2001 2006 2011 2016 2021 Anglesey 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Upper Dee 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Middle Dee 0.9 0.9 1.1 1.1 1.1 1.1 1.2 1.2 1.2 Lower Dee 1.5 1.5 1.8 1.8 1.8 1.9 1.9 2.0 2.0 Clwyd 0.2 0.2 0.3 0.3 0.3 0.3 0.3 0.3 0.3 Conwy 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Gwrfai 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Dwyfor 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Glaslyn 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Artro, Mawddach 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Dysynni 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Dyfi. Leri 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Rheidol 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Aeron, Arth 0.0 0.0 0.0 0.0 0.1 0.1 0.1 0.1 0.1 Teifi 0.3 0.3 0.4 0.4 0.4 0.4 0.4 0.4 0.4 N. Pembs 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Cleddau 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 S. Pembs 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Taf 0.3 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.5 Gwendraeth 0.1 0.1 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Upper Tywi 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Cothi 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Gwill 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Gower 0.1 0.1 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Loughor 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Tawe 0.0 0.0 0.0 0.1 0.1 0.1 0.1 0.1 0.1 Neath 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Afan, Kenfig 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Ogmore 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Thaw 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Ely 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Taff 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Rhymney 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Ebbw 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Upper Usk 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Lower Usk 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.4 0.4 Upper Wye 0.3 0.3 0.4 0.4 0.4 0.4 0.4 0.4 0.5 Lower Wye 2.1 2.1 2.4 2.5 2.5 2.6 2.7 2.7 2.8 Lugg 3.2 3.3 3.8 3.9 3.9 4.0 4.1 4.2 4.3 Monnow 0.7 0.7 0.8 0.8 0.8 0.8 0.8 0.9 0.9 IH1GH FO REC A ST TOTAL 1 11.0 11.2 12.8 1 13.1 13.4 13.7 14.1 14.4 14.7 c:\jobs\4432\private.wk1 H8 24-Jun-94 Table H.9 Amenity/Conservation demands — low growth forecast Gross average demand (MM) Subcatchment ■ 1981 1986 1991 1996 2001 2006 =. 201 r 2016 2021 Anglesey 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 o: c:\jobs\4432\private.wk1 H9 24—Jun-94 Table H.10 Amenity/Conservation demands — high growth forecast Gross average demand (Ml/d) Subcatchment 1981 1986 1991 1996 2001 2006 2011 2016 2021 Anglesey 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Upper Dee 0.0 0.0 0.2 0.2 0.2 0.2 0.2 0.3 0.3 Middle Dee 0.0 0.0 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Lower Dee 0.0 0.1 0.9 1.0 1.0 1.0 1.1 1.1 1.1 Clwyd 0.0 0.0 0.2 0.2 0.2 0.2 0.3 0.3 0.3 Conwy 0.0 0.0 0.6 0.6 0.6 0.6 0.6 0.7 0.7 Gwrfai 0.1 0.1 1.4 1.5 1.5 1.6 1.6 1.7 1.7 Dwyfor 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Glaslyn 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Artro, Mawddach 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Dysynnl 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Dyfl, Leri 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Rheidol 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Aeron, Arth 0.1 0.1 1.3 1.3 1.4 1.4 1.5 1.5 1.6 Teifi 0.0 0.1 0.9 1.0 1.0 1.1 1.1 1.1 1.2 N. Pembs 0.0 0.0 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Cleddau 0.0 0.0 0.4 0.4 0.4 0.4 0.5 0.5 0.5 S. Pembs 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Taf 0.0 0.0 0.5 0.5 0.5 0.5 0.5 0.5 0.6 Gwendraeth 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Upper Tywi 0.0 0.0 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Cothi 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Gwili 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Gower 0.0 0.0 0.5 0.5 0.6 0.6 0.6 0.6 0.6 Loughor 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Tawe 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Neath 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Afan, Kenfig 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.1 Ogmore 0.0 0.0 0.3 0.3 0.4 0.4 0.4 0.4 0.4 Thaw 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Ely 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Taff 0.0 0.1 0.8 0.8 0.8 0.9 0.9 0.9 1.0 Rhymney 0.0 0.0 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Ebbw 0.8 1.2 18.6 19.3 20.0 20.7 21.4 22.1 22.8 Upper Usk 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Lower Usk 0.0 0.1 0.8 0.9 0.9 0.9 1.0 1.0 1.0 Upper Wye 0.0 0.0 0.4 0.4 0.4 0.4 0.4 0.4 0.4 Lower Wye 0.0 0.0 0.1 0.1 0.1 0.2 0.2 0.2 0.2 Lugg 0.0 0.0 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Monnow 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 IHIGH FO REC A ST TOTAL I 1.2 1.9 28.7 29.8 30.9 31.9 33.0 34.1 35.2 c:\jobs\4432\private.wk1 H10 2 4 -Jun—94 -WATER RESOURCES CONSULTATION DOCUMENT MAIN TOPIC SUB MAPS DIAGRAMS PHOTOS HEADINGS HEADINGS HEADINGS IB Prologue Water & Wales Celts Celtic IB ind Revolution Mill IB Conflict & management IB 20th Cent Issues IB This Document IB Introduction About the NRA Statutory Responsibility Geography IB Mission Statement IB Role & Water Co's. IB Policies Striking a balance IB How we manage res’s IB Purpose of Document Asking for comment IB What is Res Planning IB Our Vision IB About Welsh History Region RV Surface Water Rainfall Isohyets RV River flows Rivers R.Wye RV Groundwater Aquifers Location Drill Rig RV Exemption RV Baseflows RV Minewaters Pellenna RV Drought RV Present Water Who uses water PWS * 5 No. Licences RV Use Private Abstract Q. RV HEP PWS History RV Transfers RV Agriculture etc. S.l. RV FCRN Canoe RV WQ RV Safeguarding Sustaining Resources RV the Environment ALF RV GPP RV Section 20 Brianne IB Licensing Policy IB Establish Min Flows IB Incentive Charges IB Env Appraisal RV Future Water Background Process RV Use Scenario Development RV Growth in Demand PWS Reg PWS RV & Deficits Private RV HEP Graphs RV Industry Graphs Brit Steel RV Agriculture Graphs RV Transfers IB Env Needs (as above) IB National Strategy Transfers Nat Map Craig Goch IB Threats N03/Climate Change IB Trees/Minewaters RV Meeting Deficits Demand Management Metering RV Leakage RV Pressure control RV Wammi RV WR Schemes Engineering Options" RV Imaginative Schemes RV Best Use of Current Schemes RV - IB The Way Precautionary Principle Reasonable need IB Forward Env Sustainability Striking a balance. IB Demand Management IB RV Comments Questionnaire RV Glossary APPENDIX I LIST OF CONSULTEES WRWRS.REP/75F/27 June 1994 I LIST OF CONSULTEES I.l GENERAL During the course of carrying out this project representatives of the following organisations have been consultees with regard to future demands for water in the Region:- National Farmers Union Ministry of Agriculture, Fisheries and Food Agricultural Development Advisory Service Associated British Ports Forest Enterprise Forest Authority Shawater Limited Welsh Office National Rivers Authority Wrexham & East Denbighshire Water Co. Chester Waterworks Co. Dwr Cymru Welsh Tourist Board WRWRS.REP/75F/27 June 1994 Page 11